TV multitronic ransmission 01J - Download...V ariable Automatic T ransmission multitronic ® 01J...
Transcript of TV multitronic ransmission 01J - Download...V ariable Automatic T ransmission multitronic ® 01J...
Variable Automatic
Transmission
multitronic® 01J
Self-Study ProgramCourse Number 951103
Audi of America, Inc.3800 Hamlin RoadAuburn Hills, MI 48326Printed in U.S.A.August 2001
Design and Function
Audi of America, Inc.Service TrainingPrinted in U.S.A.Printed 8/2001Course Number 951103
All rights reserved. All information containedin this manual is based on the latestinformation available at the time of printing andis subject to the copyright and other intellectualproperty rights of Audi of America, Inc., itsaffiliated companies and its licensors.All rights are reserved to make changes at anytime without notice. No part of this documentmay be reproduced, stored in a retrievalsystem, or transmitted in any form or by anymeans, electronic, mechanical, photocopying,recording or otherwise, nor may thesematerials be modified or reposted to other siteswithout the prior expressed written permissionof the publisher.
All requests for permission to copy andredistribute information should be referred toAudi of America, Inc.
Always check Technical Bulletins and theAudi Worldwide Repair Information Systemfor information that may supersede anyinformation included in this booklet.
Trademarks: All brand names and productnames used in this manual are trade names,service marks, trademarks, or registeredtrademarks; and are the property of theirrespective owners.
i
multitronic®
The name multitronic® stands for thenew variable automatic transmissiondeveloped by Audi. It is also commonlyknown as a CVT.
CVT is an acronymfor “Continuously VariableTransmission.”
The CVT concept improved by Audi isbased on the long-established principle ofthe chain drive transmission. According tothis principle, the reduction ratio betweenthe lowest and highest ratios can becontrolled steplessly by means of a Variator.
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Contents
This Self-Study Program provides you with informationconcerning variable automatic transmission featuresand functions.
The Self-Study Program is not a Repair Manual!
When carrying out maintenance and repair work, it isessential to use the latest technical literature.
Important/Note!
New!
Introduction ............................................................................. 1
The Transmission Concept,Specifications
Modules ................................................................................... 7
The Flywheel and Damper Assembly,Sectional View of Transmission,The Forward Clutch/Reverse Clutch withPlanet Gear Set, The Clutch Control,The Clutch Cooling System,The Auxiliary Reduction Gear Step,The Variator, The Transmission Control,The Torque Sensor, The Splash Oil Cover,The Chain, The Oil Supply,Electro-Hydraulic Control,Selector Shaft and Parking Lock,Transmission Housing Ducting andSealing Systems, Hydraulic Circuit Diagram,ATF Cooling
Control ................................................................................... 59
Transmission Control Module J217,Sensors, CAN Information Exchange on multitronic®,Auxiliary Signals/Interface, Functional Diagram,Dynamic Control Program
Service.................................................................................... 91
Towing, Special Tools
Teletest ................................................................................... 95
Audi Variable Automatic Transmission Teletest
iii
1
Introduction
Transmissions are required to matchthe torque characteristics of the engine tothe vehicle.
Usually, multi-step reduction gears areused, such as manual transmissions,automated manual transmissionsand multi-step automatic reduction gears.A multi-step reduction gear alwaysrepresents a compromise betweenhandling dynamics, fuel economy anddriving comfort.
In an engine, torque flow is notintermittent but continuous. A variabletransmission ratio is, therefore, ideal forengine power utilization.
The CVT designs which have been availableon the market until now are based uponthe “chain drive principle.” Because oftheir limited abilities to transfer power,
however, they have only been suitable forsubcompact cars and vehicles in the lowermid-range segment with low engineperformance.
Audi chose the belt/chain drive principlefor the development of its CVT design,because it is the most advanced form oftransmission available today.
Audi’s objective was to develop a CVTdesign for high-performance premiumsegment vehicles that sets new standardsin terms of driving performance and fueleconomy, as well as in handling dynamicsand comfort.
Audi is the first to present a CVTthat can be used in combinationwith 3.0-liter V6 engine with220 bhp (162 kW) and 221 lbs-ft(300 Nm) of torque.
Manual Transmission multitronic® CVTStepped Mode O1V / O1N
P
R
N
D
P
R
N
4
3
2
D
R 1 3 5
2 4
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2
Introduction
The Transmission Concept
Engine torque is transmitted to thetransmission through either a flywheel anddamper assembly or a dual-mass flywheeldepending on engine version.
There is one “wet“ plate clutch for forwardtravel and one for reverse travel; both actas starting clutches.
The rotational direction for reverse ischanged by means of a planetary gear train.
TransmissionControlModule J217
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The engine torque is transmitted to theVariator via an auxiliary reduction gear stepand transferred from there to the final drive.
The electro-hydraulic control, together withthe Transmission Control Module J217,forms a unit which is located in thetransmission housing.
The Tiptronic function provides six“speeds“ for manual gear selection.
Flywheel andDamper Assembly
ReverseGear Clutch
Auxiliary ReductionGear Step
Variatorwith Chain
PlanetaryGear Train
ForwardClutch
HydraulicControlModule
3
Introduction
The key component part of themultitronic® is the Variator. It allowsreduction ratios to be adjusted continuouslybetween the starting torque multiplicationratio and the final torque multiplication ratio.
As a result, a suitable ratio is alwaysavailable. The engine can always operatewithin the optimum speed range regardlessof whether it is optimized for performanceor fuel economy.
The Variator has two tapereddisc pairs — a set of primary pulleys(pulley set 1) and a set of secondary pulleys(pulley set 2) — as well as a special chainwhich runs in the V-shaped gap betweenthe two tapered pulley pairs. The chain actsas a power transmission element.
Pulley set 1 is driven by the enginethrough an auxiliary reduction gear step.Engine torque is transmitted via thechain to pulley set 2 and from here to thefinal drive.
One of the tapered pulleys in each of thesets of pulleys can be shifted on the shaftfor variable adjustment of the chain trackdiameter and transmission ratio.
The two sets of pulleys must be adjustedsimultaneously so that the chain is alwaystaut and the disc contact pressure issufficient for power transmission purposes.
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Set of Primary Pulleys(Pulley Set 1)
Set of Secondary Pulleys(Pulley Set 2)
Downforce
Drive
Wide
Narrow
Variator in Starting Torque Ratio
Variator in Final Torque Ratio
4
Introduction
multitronic® for
Maximum Comfort
In automatic mode, any ratio is possiblewithin the bounds of the TCM.The factors that determine rpm are driverinput (accelerator pedal position andactuation rate) and rolling resistance.Transmission ratios are adjusted completelyfree of jolts without interruption in tractivepower flow.
In the Tiptronic function, there are sixdefined shifting characteristics for manual
gear selection. The driver can thereforechoose handling dynamics to suit his orher personal preferences. This feature isparticularly useful on downhill gradesfor example, as the driver can determinethe engine braking effect by selectivedown-shifting.
Top speed is achieved in 5th gear.The 6th gear is configured as an economygear or overdrive.
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SSP 228/038
5
Introduction
The Tiptronic can also be operatedfrom the steering wheel as an optionon some vehicles.
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SSP 228/015
6
Introduction
All the specifications in thisSelf-Study Program referonly to the multitronic® withthe code DZN.
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Specifications
Designation: multitronic®01J
Factory Designation: VL 30
Code: DZN
Maximum Transferable Torque: Maximum 229 lbs-ft (310 Nm)
Range of Ratios of the Variator: 2.40 : 1 to 0.40 : 1
Spread: 6
Ratio of Auxiliary Reduction Gear Step: 51/46 = 1.109 : 1
Final Drive Ratio: 43/9 = 4.778 : 1
Operating Pressure of Oil Pump: Maximum Approximately 870 psi (6 000 kPa)
ATF for multitronic®: G 052 180 A2
Axle Oil for multitronic®: G 052 190 A2
Gear Oil Quantities:ATF New Filling (Including ATF Cooler and ATF Filter) Approximately 7.9 qt (7.5 liters)ATF Change Approximately 4.8 qt (4.5 liters)Axle Oil Approximately 1.4 qt (1.3 liters)
Gross Weight (Without Flywheel): Approximately 194 lbs (88 kg)
Overall Length: Approximately 24 in (610 mm)
7
Modules
Damper
The Flywheel
and Damper Assembly
In reciprocating engines, the unevennessof the combustion sequence inducestorsional vibration in the crankshaft.
This torsional vibration is transmittedto the transmission and results inresonant vibration, producing noise andoverloading components inthe transmission.
The flywheel and damper assemblyand the dual-mass flywheel dampentorsional vibration and ensure theengine runs quietly.
In the 3.0-liter V6 engine, engine torque istransmitted to the transmission through aflywheel and damper assembly.
Because four-cylinder engines do notrun as smoothly as six-cylinder engines,a dual-mass flywheel is used infour-cylinder engines.
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Dual-MassFlywheel
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Flywheel
8
Modules
Sectional View of Transmission
For better representation,the oil pump and the transfercase are shown folded on thecutting plane.
9
Modules
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Housing, Screws, Bolts
Hydraulic Parts/Control
Electronic Transmission Control
Shafts, Gears
Plate Clutches
Pistons, Torque Sensors
Bearings, Washers, Circlips
Plastics, Seals, Rubber
Color Definitions
10
Modules
The Forward Clutch/Reverse
Clutch with Planet Gear Set
In contrast to multi-step automatictransmissions, such as the 01V, which usea torque converter, separate clutches areused for forward and reverse travel in theAudi CVT design. These “wet plateclutches” are also used to executegearshifts in multi-step automatictransmissions. They are used for drivingoff and transmitting the torque to theauxiliary reduction gear step. The drive-offprocess and torque transmission aremonitored electronically and regulatedelectro-hydraulically.
The electro-hydraulically controlled wetplate clutch has the following advantagesover a torque converter:
• Low weight
• Very little installation space is required
• Adaptation of clutch engagementcharacteristic to driving situation
• Adaptation of slip torque todriving situation
• Protective function in the event ofoverloading or misuse
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Reverse Clutch
ForwardClutch
Planet Carrier
Input Pulley Set 1(Auxiliary Reduction Gear Step)
Forward Clutch/Reverse Clutchwith Planetary Gear Train
Planetary GearsTransmissionInput Shaft
Ring Gear
11
Modules
The Planetary Gear Train
The planetary gear train is constructed as aplanet reversing gear set and its onlyfunction is to change the rotational directionof the transmission for backing up.
The reduction ratio in the planetary geartrain is 1:1 when backing up.
Assignment of Components
The sun gear (input) is linked to thetransmission input shaft and the steelplates on the forward clutch.
The planet carrier (output) is linked to thedrive gear, the auxiliary reduction gear step,and the lined plates on the forward clutch.
The ring gear is connected to theplanetary gears and the lined plates on thereverse clutch.
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Steel Plates and Lined Plateson Forward Clutch
Ring GearSteel Plates and Lined Plateson Reverse Clutch
Sun Gear Input Pulley Set 1(Auxiliary ReductionGear Step)
Planet Carrier withPlanetary Gears
TransmissionInput Shaft
12
Modules
Power Flow in the Planetay Gear Train
Torque is transferred to the planetary geartrain via the sun gear which is connected tothe input shaft and drives the planetarygears 1.
Planetary gears 1 drive planetary gears 2,which are in mesh with the ring gear.
Planet Carrier
The planet carrier (output planetary geartrain) is stationary because it acts as theinput for the auxiliary reduction gear stepand the vehicle is still not moving.
The ring gear idles and rotates athalf engine speed in the direction ofengine rotation.
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Direction of Rotation of Components when
Engine is Running and Vehicle is Stationary
Transmission Input Shaftwith Sun Gear
Ring Gear
Planetary Gear 2Planetary Gear 1
13
Modules
Power Flow During Forward Travel
The steel plates on the forward clutch arelinked to the sun gear and the lined platesare linked to the planet carrier.
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When the forward clutch is engaged, itconnects the transmission input shaft tothe planet carrier (output). The planetarygear train is locked and rotates in the samedirection as the engine; the torquetransmission ratio is 1:1.
Oil Pressure for ClutchTorque Flow
Forward Clutch
Planetary Gear Train
14
Modules
Power Flow in Reverse
The lined plates of the reverse clutchare connected to the ring gear and thesteel plates are connected to thetransmission housing.
When the reverse clutch engages, it holdsthe ring gear and thereby prevents thetransmission housing from rotating.
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Reverse Clutch
Torque is then transmitted to the planetcarrier, which begins to rotate in theopposite direction to the engine. Thevehicle moves in reverse.
Road speed is limitedelectronically when thevehicle is in reverse.
The Variator remains in thestarting torque ratio.
Oil Pressure for ClutchTorque Flow
Ring Gear
15
Modules
Accelerator Pedal AngleEngine SpeedNominal Engine SpeedTransmission Input Speed, Pulley Set 1Transmission Output Speed, Pulley Set 2
20
40
60
80
100
1000
01 2 3 4 5 6 7 8 9 10
2000
3000
4000
0
Accelerator Pedal100% Depressed
Eng
ine
Spe
ed
Time in Seconds SSP 228/052
20
40
60
80
100
1000
01 2 3 4 5 6 7 8 9 10
2000
3000
4000
0
Eng
ine
Spe
ed
Time in Seconds SSP 228/053
AcceleratorPedal 60%Depressed
20
40
60
80
100
1000
01 2 3 4 5 6 7 8 9 10
2000
3000
4000
5000
6000
0
Eng
ine
Spe
ed
Time in Seconds SSP 228/054
Accelerator Pedal100% Depressed+ Kickdown
The Clutch Control
Clutch Engagement
Engine speed controls CVT clutchengagement to initiate vehicle motion.
The accelerator pedal angle and applicationspeed set by the driver and the control maprequirements of the Transmission ControlModule J217 determine the clutchengagement characteristics for eachvehicle start from rest.
Depending upon the specific driver inputsfor each start, the Transmission ControlModule J217 sets a nominal engine speedat which clutch engagement will take place.
With the vehicle at rest, moderateapplication of the accelerator pedal(characterized by slow movement to asmall accelerator pedal angle) initiates thetransition from engine idling speed toclutch engagement speed at a relativelylow engine speed. Short clutch slip timesand low engine speed at clutchengagement will provide the best fueleconomy.
For a performance start from rest, heavyapplication of the accelerator pedal (quickmovement to a large accelerator pedalangle) initiates the transition from engineidling speed to clutch engagement enginespeed at a higher engine rpm. The greatertorque developed at higher engine rpmyields faster vehicle acceleration.
Differences in engine type andperformance characteristics also have aneffect on CVT clutch engagementcharacteristics.
16
Modules
Electronic Control
The following parameters are used forclutch control:• Engine speed• Transmission input speed• Accelerator pedal position• Engine torque• Brake applied• Transmission oil temperatureThe Transmission Control Module J217calculates the nominal clutch pressurefrom these parameters and determinesthe control current for Pressure ControlValve -1- for Automatic Transmission N215.The clutch pressure, and thereforethe engine torque to be transmitted by theclutch, changes almost in proportion tothe control current (refer to “HydraulicControl,” page 17).Automatic Transmission Sender -1- forHydraulic Pressure G193 registers theclutch pressure (actual clutch pressure) inthe hydraulic control. Actual clutch pressureis continuously compared to the nominalclutch pressure calculated by theTransmission Control Module J217.The actual pressure and specified pressureare checked continuously for plausibilityand corrective action is taken if these twovalues deviate from one another by morethan a certain amount (refer to “SafetyShut-Off,” page 18).To prevent overheating, the clutch iscooled and clutch temperature is monitoredby the Transmission Control Module J217(for more detailed information, refer to“The Clutch Cooling System,” page 23, and“Overload Protection,” page 18).
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Transmission ControlModule J217
Automatic Transmission Sender-1- for Hydraulic Pressure G193
Pressure Control Valve -1- forAutomatic Transmission N215
17
Modules
Hydraulic Control
Clutch pressure is proportional to enginetorque and is not dependent on thesystem pressure.A constant pressure of approximately73 psi (500 kPa) is applied by the pilotpressure valve to the Pressure ControlValve -1- for Automatic Transmission N215.Pressure Control Valve -1- for AutomaticTransmission N215 produces a controlpressure which controls the position of theclutch control valve depending on thecontrol current calculated by theTransmission Control Module J217.A high control current results in a high
control pressure.
The clutch control valve controls the clutchpressure and therefore also regulates theengine torque to be transmitted.
The clutch control valve is suppliedwith system pressure and produces clutchpressure in accordance with the activationsignal from Pressure Control Valve -1- forAutomatic Transmission N215.A high control pressure results in a high
clutch pressure.
The clutch pressure flows via the safetyvalve to the manual selector valve.The manual selector valve transfers clutchpressure either to the forward clutch(position D) or to the reverse clutch(position R), depending on the selectorlever position. The non-pressurizedclutch is vented into the oil sump.In selector lever positions N and P, thesupply is shut off via the manual selectorvalve and both clutches are vented intothe oil sump.
ReverseClutch
ManualSelectorValve
ForwardClutch
SafetyValve
Pressure ControlValve -1- for AutomaticTransmission N215
PilotPressureValve
ClutchControlValve
P R N D
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ATF Depressurized
Clutch PressureSupply Pressure
Pilot Control PressureControl Pressure
In the Oil Sump
18
Modules
Safety Shut-Off
A safety-critical malfunction has occurredif actual clutch pressure is clearly higherthan specified clutch pressure. In this case,the clutch is depressurized regardless ofthe manual selector valve position andother system states.
A safety shut-off is implemented viathe safety valve and enables the clutchto open quickly.
The safety valve is activated by SolenoidValve 1 N88. At control pressures aboveapproximately 58 psi (400 kPa), the supplyto the clutch control valve is shut off andthe connection to the manual selectorvalve in the oil sump is vented.
Overload Protection
Using a model calculation, the TransmissionControl Module J217 calculates the clutchtemperature from clutch slip, engine torqueto be transmitted, and transmission oiltemperature. Engine torque is reduced ifthe measured clutch temperature exceedsa defined threshold because of excessload on the clutch.
Engine torque can be reduced to the upperend of the idling speed range. It is possiblethat the engine will not respond to theaccelerator pedal for a short period of time.The clutch cooling system ensures a shortcooling-down time. Maximum enginetorque is quickly available again. Overloadof the clutch is almost impossible.
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Switched Position After Safety Shut-Off
Vented into Oil Sump/Depressurized
Clutch Pressure
Supply Pressure
Pilot Control Pressure
Control pressure
In the Oil Sump
ForwardClutch
ManualSelectorValve
SafetyValve
ClutchControlValve
SolenoidValve 1N88
P RN D
ReverseClutch
19
Modules
Clutch Control when Vehicle
Is Stationary (Slip Control)
The slip control function sets the clutch to adefined slip torque (clutch torque) when theengine is running at idling speed and a driveposition is selected. The vehicle behaves inthe same way as an automatic transmissionwith a torque converter.
Selective clutch pressure adaptation resultsin an input torque which causes the vehicleto ”creep.”
Input torque is varied within defined limitsdepending on vehicle operating state andvehicle road speed. The contact pressureapplied by the taper pulleys is sensed byAutomatic Transmission Sender -2- forHydraulic Pressure G194. This informationis used for precision clutch torque control.
BrakePedal NotPressed
Because contact pressure is proportional tothe actual engine input torque presentat pulley set 1, clutch torque can beprecisely calculated and controlled usingAutomatic Transmission Sender -1- forHydraulic Pressure G193 (for more detailedinformation, refer to “The Torque Sensor,”page 33).
Slip control allows the vehicle tobe maneuvered when parkingwithout pressing the acceleratorpedal and therefore enhancesdriving comfort.
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Automatic TransmissionSender -1- forHydraulic Pressure G193
29.5 psi(40 Nm)
Automatic TransmissionSender -2- forHydraulic Pressure G194
20
Modules
Special Feature of the Slip Control
A special feature of the slip control isthe reduction of slip torque when thevehicle is stationary and the brakes areactuated. As a result, the engine is notrequired to develop so much torque (theclutch is also open wider).
This has a positive effect on fuel economy.Noise from the engine running at idlespeed when the vehicle is stationary isreduced and much less pressure has tobe applied to the brake pedal to stopthe vehicle.
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11.1 psi(15 Nm)
If the vehicle rolls back when standingon a slope with only light pressureapplied to the brake, the clutch pressureis increased to immobilize the vehicle (“hill-holder” function).
By using two transmission output speedsenders (Sender for Transmission OutputRPM G195 and Sender -2- for TransmissionOutput RPM G196) it is possible todistinguish between forward travel andreverse travel, which makes the hill-holderfunction possible (for further information,please refer to “Sensors,” page 63).
BrakePedalPressed
Automatic TransmissionSender -1- forHydraulic Pressure G193
Automatic TransmissionSender -2- forHydraulic Pressure G194
0 (0)
37 (50)
74 (100)
111 (150)
148 (200)
184 (250)
221 (300)
10000 2000 3000 4000 5000 6000 7000
Eng
ine
Torq
ue in
lbs-
ft (N
m)
21
Modules
The Micro-Slip Control
The micro-slip control serves to adapt theclutch control (see description of adaptationprocess, page 22) and dampen the torsionalvibration induced by the engine.
In the part-throttle range, the clutchcharacteristics are adapted up to an enginetorque of 118 lbs-ft (160 Nm).
In the engine speed range up toapproximately 1800 rpm and at enginetorques up to approximately 162 lbs-ft(220 Nm), the clutch operates in what isknown as “micro-slip” mode. In thisoperating mode, a slip speed (speeddifferential) of approximately 5 rpm to 20rpm is maintained between thetransmission input shaft and pulley set 1.
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For this purpose, the Transmission ControlModule J217 compares the signalgenerated by Sensor for Transmission RPMG182 with the engine speed, makingallowance for the auxiliary reduction gearstep. Sensor for Transmission RPM G182registers the rotation of pulley set 1.
As the term “micro-slip”suggests, clutch slip is kept ata minimum so no noticeablepenalties in lining wear and fueleconomy occur.
Engine Speed in RPM
Approximately1800 RPM
Clutch Closed
Micro-Slip Control Range
Adaptation Range During Micro-Slip Control:Up to Approximately 118 lbs-ft (160 Nm)
22
Modules
Clutch Control Adaptation
To be able to control the clutch comfortablyin any operating state and throughout itsservice life, the relationship betweencontrol current and clutch torque has to beupdated continuously.
This is necessary because thecoefficients of friction of the clutchesare constantly changing.
The coefficient of friction is dependent onthe following factors:
• Transmission oil (quality, aging, wear)
• Transmission oil temperature
• Clutch temperature
• Clutch slip
To compensate for these influences andoptimize clutch control, the relationshipsbetween control current and clutch torqueare adapted in slip control mode and in thepart-throttle range.
Adaptation in Slip Control Mode
(Brake Pressed):
As mentioned already, a defined clutchtorque is set in slip control mode.The Transmission Control Module J217observes the relationship between thecontrol current from Pressure Control Valve-1- for Automatic Transmission N215 andthe data from Automatic TransmissionSender -2- for Hydraulic Pressure G194(contact pressure) and stores these data.The actual data are used for calculatingnew characteristics.
Here, “adaptation” meanslearning new pilot control values.
Adaptation in Part-Throttle Range
In the part-throttle range, adaptation isperformed in micro-slip control mode.In this operating mode the TransmissionControl Module J217 compares the enginetorque from the Motronic Engine ControlModule J220 to the control current fromPressure Control Valve -1- for AutomaticTransmission N215 and stores these data.The actual data are used for calculatingnew characteristics (see “Micro-SlipControl,” page 21).
Summary:
The adaptation function serves to maintaina constant clutch control quality.
The adaptation data also have an effecton the calculation of clutch pressure athigher transmission torques (clutch fullypositively engaged).
High clutch pressures are not required,which ultimately has a positive effecton efficiency.
23
Modules
The Clutch Cooling System
The clutches are cooled by a separateoil flow in order to protect them fromexposure to excessively high temperatures(particularly when driving away underhard acceleration).
To minimize power losses due to clutchcooling, the cooling oil flow is directedwhere it is needed by a cooling oil controlmodule integrated into the valve body.
Additional cooling oil is supplied by asuction jet pump (entrainment pump)without placing a demand on oil
Forward Clutch
SSP 228/064
pump capacity.
To optimize clutch cooling, the cooling oilflows only to the power-transmitting clutchpulley set.
The cooling oil and the pressurized oil ofthe forward clutch flow through the hollowtransmission input shaft. The two oilcircuits are separated from one another bya steel tube, the “inner part.”
An “oil divider” located at the oil outletbores on the transmission input shaftguides the cooling oil flow to the forwardclutch and the reverse clutch.
Oil Divider withDiaphragm Spring andStop Ring with Openings
Diaphragm SpringDistributor Disc
Inner Part
Stop Ring
Oil Divider
Reverse Clutch
24
Modules
Cooling the Forward Clutch
If the forward clutch is engaged, thecylinder (thrust plate) of the forward clutchpresses the oil divider back.
In this position, the cooling oil flows pastthe front face of the oil divider and throughthe forward clutch.
Cooling the Reverse Clutch
If the forward clutch is not operated(when the engine is running at idling speedor when the reverse clutch is operated),the oil divider is in its basic position.
In this position, the cooling oil flows to theoil divider and is rerouted to the reverseclutch by a distributor plate. Branches in thedistributor pulley duct cooling oil to theplanetary gear train and provide thenecessary lubrication there.
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Forward Clutch Reverse Clutch
Cylinder
Oil Pressure for Clutch
Clutch Cooling Oil Flow
25
Modules
Hydraulic Clutch Cooling Control
The clutch cooling system cuts inat the same time as the clutch controlis activated.
The Transmission Control Module J217applies a defined control current toSolenoid Valve 1 N88. This produces acontrol pressure which switches the clutchcooling valve.
SSP 228/045
The clutch cooling valve transfers pressurefrom the cooler return pipe to the suctionjet pump (entrainment pump).
The pressurized oil is used to operate thesuction jet pump (entrainment pump) (forfurther details, refer to “The Suction JetPump (Entrainment Pump),” page 46).
Pilot Control Pressure
Control Pressure
In the Oil Sump
To Manual Selector Valve
To Cooler Return Pipe
SafetyValve
SolenoidValve 1N88
Pressure ControlValve -1- for AutomaticTransmsiion N215
ClutchCoolingValve
PilotPressureValve
Suction Jet Pump(Entrainment Pump)with Check Valve
To theClutches
ATF Depressurized
Cooling Oil Flow
Oil from Cooler Return Pipe
26
Modules
The Auxiliary Reduction Gear Step
Due to constraints on space, torque istransmitted to the Variator through anauxiliary reduction gear step.
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The auxiliary reduction gear step hasdifferent reduction ratios to accommodatedifferent engines to the transmission. As aresult, the Variator is operated within itsoptimum torque range.
PlanetaryGear Train
Pulley Set 1
Auxiliary ReductionGear Step
27
Modules
The Variator
The basic operating principle of theVariator has been explained on page 3. Thespecial features and functions of themultitronic® Variator are described on thefollowing pages.
The Concept of the Variator Used in the
multitronic®
The operation of the Variator is based onwhat is known as the dual-piston principle.A special feature of the multitronic®Variator is the torque sensor integrated inpulley set 1 (for more detailed informationrefer to “The Torque Sensor,” page 33).
Pulley sets 1 and 2 each have a separatepressure cylinder for pressing the taperpulleys as well as a separate variabledisplacement cylinder for transmissionratio adjustment.
The dual-piston principle makes it possibleto change the transmission ratio veryquickly by applying a small amount ofpressure. This ensures that the taperpulleys maintain sufficient contact pressureat a relatively low oil pressure level.
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Starting Torque Ratio
Pulley Set 2
Pulley Set 1
ChainTorque Sensor
28
Modules
Adjustment
A suitable supply of pressurized oil isrequired due to the heavy demands on theadjustment dynamics. To minimize therequired quantity of oil, the variabledisplacement cylinders have a smallersurface area than the pressure cylinders.Therefore, the quantity of oil needed foradjustment is relatively small.
This makes high adjustment dynamics andhigher efficiency possible despite the lowdelivery rate of the oil pump.
The diaphragm springs in pulley set 1and the coil springs in pulley set 2 createa defined basic chain tension (contactpressure) when the hydraulic systemis depressurized.
In the depressurized state, the Variatorfor the starting torque ratio is adjusted bythe spring force of the coil springs inpulley set 2.
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End Torque Multiplication Ratio (Overdrive)
Pressure Cylinder Diaphragm Spring
Torque Sensor Variable Taper Pulley
Pulley Set 1
VariableDisplacementCylinder
Pulley Set 2
Variable Taper PulleyPressure Cylinder
Pressure Spring
VariableDisplacementCylinder
29
Modules
Contact Pressure
High contact pressures are requiredbetween the taper pulley and the chain totransmit the torque the engine develops.The contact pressure is produced byadjusting the oil pressure in the pressurecylinder as appropriate.
According to the principles of hydraulics, aresultant force (contact pressure) can bevaried as a function of pressure andeffective area.
The pressure cylinders have a largersurface area and can therefore apply therequired contact pressure with less oilpressure. The relatively low oil pressure isalso more efficient.
Towing
When the vehicle is being towed, pulley set2 drives pulley set 1 and there is a dynamicpressure buildup in the variabledisplacement cylinder and pressure cylinderof the pulley sets.
The system is designed in such a waythat the reduction ratio is adjusted toapproximately 1:1 by the dynamic pressurebuild-up in the Variator. Pulley set 1 andthe planetary gear train are thus protectedfrom excessively high engine speeds.
The diaphragm springs in pulley set 1 assistwith this process.
For more detailed informationregarding dynamic pressurebuild-up, refer to “The SplashOil Cover,” page 38.
Also observe the towinginformation given in “Towing,”page 91.
SSP 228/081
DiaphragmSpring inPulley Set 1
SSP 228/080
Resultant Force1124 lbs (5 000 N)
Effective Area15.50 in2
(100 cm2)
Pressure72.5 psi(500 kPa)
Resultant Force1124 lbs (5 000 N)
Effective Area7.75 in2 (50 cm2)
Pressure 145 psi(1 000 kPa)
30
Modules
The Transmission Control
Electronic Control
The Transmission Control Module J217has a dynamic control program forcalculating the nominal transmission inputspeed. It is an improved version of thedynamic shift program (DSP) already beingused in multi-step automatic transmissions.The driver input and vehicle operating stateare evaluated to provide the best gear ratioin every driving situation (see “DynamicControl Program,” page 82).
The dynamic control program calculates anominal transmission input speeddepending on conditions.
The Sensor for Transmission RPM G182registers the actual transmission inputspeed at pulley set 1.
The Transmission Control Module J217calculates a control current for PressureControl Valve -2- for AutomaticTransmission N216 based on an actual-value/setpoint comparison. PressureControl Valve -2- for AutomaticTransmission N216 produces a controlpressure for the hydraulic reduction valvewhich is almost proportional to thecontrol current.
Transmission control is monitored bychecking the plausibility of the signals fromSensor for Transmission RPM G182 andSender for Transmission Output RPM G195as well as the engine speed.
SSP 228/076
TransmissionControl Module J217
Pressure Control Valve -2- forAutomatic Transmission N216
Sensor forTransmissionRPM G182
Sender forTransmissionOutput RPM G195
31
Modules
SSP 228/076
Hydraulic Transmission Control
Pressure Control Valve -2- for AutomaticTransmission N216 is supplied witha constant pressure of approximately73 psi (500 kPa) by the pilot pressurevalve. Pressure Control Valve -2- forAutomatic Transmission N216 producesa control pressure corresponding tothe control current calculated by theTransmission Control Module J217, whichinfluences the position of the hydraulicreduction valve.
A high control current leads to a highcontrol pressure.
The hydraulic reduction valve transfersthe adjusting pressure to the variabledisplacement cylinder of pulley set 1 or 2,depending on the control pressure.
Pulley Set 1
Starting Torque Ratio
Pulley Set 2
HydraulicReductionValve
PressureControl Valve-2- forAutomaticTransmissionN216
PilotPressureValve
From theOil Pump
Vented into Oil Sump
Oil Supply
Pilot Control Pressure
Control Pressure
In the Oil Sump
32
Modules
The hydraulic reduction valve is closed at acontrol pressure of between approximately26 and 32 psi (180 and 220 kPa). At a controlpressure of less than 26 psi (180 kPa), theadjusting pressure is transferred to variabledisplacement cylinder at pulley set 1, andthe variable displacement cylinder of pulleyset 2 is simultaneously vented to theoil sump. The Variator shifts the reductionratio towards the end torque multiplictionratio (overdrive).
If the control pressure is greater than32 psi (220 kPa), the adjusting pressure istransferred to the variable displacementcylinder at pulley set 2 and the variabledisplacement cylinder at pulley set 1 issimultaneously vented to the oil sump.The Variator shifts the reduction ratiotowards the starting torque ratio.
SSP 228/084
End Torque Multiplication Ratio (Overdrive)
Pulley Set 1
Pulley Set 2
HydraulicReductionValve
PressureControlValve -2- forAutomaticTransmissionN216
PilotPressureValve
From the Oil Pump
Vented into Oil Sump
Oil Supply
Pilot Control Pressure
Control Pressure
In the Oil Sump
33
Modules
The Torque Sensor
Contact Pressure Control
As mentioned before, a suitable oilpressure in the pressure cylinder gives aresultant contact pressure of the taperpulleys. If the contact pressure is too low,slippage of the chain will occur and thechain and pulley sets will be damaged. Anexcessively high contact pressure, on theother hand, will result in loss of efficiency.
The object, therefore, is to set the contactpressure of the taper pulleys as accuratelyand safely as possible according torequirements.
RampShell 1
SSP 228/021
A hydro-mechanical torque sensorintegrated in pulley set 1 statically anddynamically registers the actual torquetransmitted to a high degree of accuracyand sets the correct oil pressure in thepressure cylinders.
The engine torque is transferredto the Variator by the torquesensor only. The contact pressureis controlled hydro-mechanicallyby the torque sensor.
Ramp Shell 2
Pulley Set 1
RampShell 2
34
Modules
Design and Function
The torque sensor essentially comprisestwo shells with seven ramps betweenwhich steel balls are mounted in bearings.Ramp shell 1 is form-fitted to the outputgear of pulley set 1 (output gear wheel ofauxiliary reduction gear step). Ramp shell 2is connected to pulley set 1 by a groovedgearing that allows axial movement and issupported by the torque sensor piston. Thetorque sensor piston serves to regulate thecontact pressure and houses torque sensorspaces 1 and 2.
The shells can be rotated radiallytowards one another, converting thetorque to an axial force (due to the balland ramp geometry).
This axial force acts upon ramp shell 2 andmoves the torque sensor piston which is incontact with the shell.
The control edge of the torque sensorpiston now closes or opens the outlets intorque sensor space 1.
The axial force generated by thetorque sensor serves as a controlforce which is proportional to theengine torque.
The pressure which builds upin the pressure cylinder isproportional to the control force.
SSP 228/022
Torque Sensor Piston
Torque Sensor Space 1
Torque Sensor Space 2
Ramp Shell 1
Grooved Gearing
Ramp Shell 2
35
Modules
Torque sensor space 1 is directly connectedto the pressure cylinder.
The system is designed so the axial forcegenerated as a product of engine torqueand the pressure in the pressure cylinderform a force equilibrium.
In constant conditions of vehicle operation,the outlet bores are only partially closed.The pressure drop produced by opening theoutlet bores (torque sensor) modulates thepressure in the pressure cylinder.
If input torque increases, the outlet boresare initially closed further by the controledge. The pressure in the pressure cylinderrises until a force equilibrium again exists.
If input torque decreases, the outlet boresare opened further. The pressure in thepressure cylinder decreases until the forceequilibrium is restored.
SSP 228/057
PressureCylinder
SSP 228/056
Torque SensorSpace 1
OutletBore
PressureCylinder
ControlEdge
OutletBore
100
75
50
25
02.4 1 0.4
36
Modules
At peak torque levels, the control edgecloses off the outlet bores. If the torquesensor moves any further, it acts as an oilpump. The displaced oil volume causes arapid rise in the pressure inside thepressure cylinder and immediately adjuststhe contact pressure.
Extremely high peak torques canoccur when the vehicle drivesover a pot-hole or if thecoefficient of friction of the roadsurface fluctuates considerably(transitions from black ice toasphalt for example).
Adaptation of contact pressure
depending on transmission ratio
The contact pressure exerted by the taperpulleys depends not only on the inputtorque but also on chain track radius and,therefore, on the actual reduction ratio ofthe Variator.
As the diagram shows, the starting torqueratio (clutch engagement) requires thegreatest contact pressure.
The radius of the chain is smallest in pulleyset 1. For power transmission, only a smallnumber of cradle type pressure pieces arein mesh despite the high input torque.
Therefore, a higher contact pressure isapplied by the taper pulleys until a definedreduction ratio of 1:1 is exceeded.
OutletBore
SSP 228/046
SSP 228/058
PressureCylinder
Con
tact
Pre
ssur
e in
%
Required Contact Pressurefor 25% Torque Requirement
VariatorRatio
Overdrive
Starting Torque Ratio
Overdrive
Starting Torque Ratio
Required Contact Pressurefor 100% Torque Requirement
Contact Pressure
37
Modules
Function and Mode of Operation
The ratio-dependent contact pressureis adapted in torque sensor space 2.The pressure level in the pressure cylinderis varied by increasing or decreasing thepressure in torque sensor space 2.The pressure in torque sensor space 2is controlled by two transverse holes inthe shaft of pulley set 1. These holes areopened or closed through axialdisplacement of the variable taper pulley.
The transverse holes are open when theVariator is in the starting torque ratio(torque sensor space 2 is depressurized).
When the Variator changes the ratioto end torque multipliction ratio (overdrive),the transverse holes are shut off initially. Ata defined reduction ratio, the left-handtransverse hole is opened to the pressurecylinder through corresponding holes in thevariable taper pulley.
This allows the oil pressure to betransferred from the pressure cylinder intotorque sensor space 2. This pressurecounteracts the axial force of the torquesensor and moves the torque sensor pistonto the left.
The control edge opens up the outlet boresfurther, reducing the oil pressure inside thepressure cylinder.
The main advantage of the two-stagepressure adaptation process is that a lowcontact pressure can be utilized in themid-ratio range which increases efficiency(refer to illustration SSP 228/046,previous page).
SSP 228/060
Torque Sensor Piston
SSP 228/059
Transverse HolesTorque Sensor Space 2
Variable Taper Pulley
Torque Sensor Space 2Bore
Bore
38
Modules
The Splash Oil Cover
Another special feature of the Variator isthe “splash oil cover” on pulley set 2 whichcounteracts the dynamic pressure buildupin the pressure cylinder.
At high engine speeds, the transmission oilin the pressure cylinder is subjected to highrotation-induced centrifugal forces, whichleads to a rise in pressure. This process isknown as “dynamic pressure buildup.”
A dynamic pressure buildup is undesirablebecause it unduly increases the contactpressure and has an adverse effect ontransmission control.
The oil confined in the splash oil cover issubjected to the same dynamic pressurebuildup as in the pressure cylinder. Thedynamic pressure buildup in the pressurecylinder is compensated by this.
The splash oil chamber receives its oilsupply directly from the hydraulic controlmodule through an oil injection hole. Oil iscontinuously injected into the splash oilchamber inlet through this hole.
A reduction in volume inside the splash oilchamber (when varying the transmissionratio) causes the oil to be dischargedthrough the supply inlet.
SSP 228/061
Oil Injection Hole
Splash Oil CoverPulley Set 2
Pressure Cylinder
Splash Oil Chamber
39
Modules
The Chain
The chain is a key component part of theVariator of the multitronic®.
This is the first time that a chain has beenused as a driving means in a CVT.
The chain is a new development and hasthe following advantages over conventionaldriving means such as sliding link beltsor V-belts:
• Very small track radii make possible alarge “spread” despite the small size ofthe Variator.
• High transferable torque.
• High efficiency.
Pulley Set 1
SSP 228/026
The spread indicates the rangeof ratios which a transmissionprovides.
The spread is specified as a ratio.The starting torque ratio dividedby the spread equals to the endtorque multiplication ratio.In general a large spread is anadvantage because both a highstarting torque ratio (for goodperformance) and a low endtorque multiplication ratio (for lowfuel consumption) are available.This applies in particular to theCVT concept, since practicallyall intermediate steps areavailable and no ratio steps areout of place.
Pulley Set 2
Chain
40
Modules
Design and Function
On a conventional chain, the chain linkplates are interconnected by joint pins witha slip fit. For torque transmission, gearteeth move into engagement with the pinsbetween the chain link plates.
The CVT chain uses a
different technology.
The CVT chain has adjacent rows of chainlink plates linked continuously with cradletype pressure pieces (two per link).
On the CVT chain, the cradle type pressurepieces are “jammed” between the taperpulleys of the Variator as the taper pulleysare pressed toward one another.
The torque is transmitted only by thefrictional force between the ends of thecradle type pressure pieces and thecontact faces of the taper pulleys.
This is how it works:
Each of the cradle type pressure pieces ispermanently connected to a row of linkplates so that it cannot be twisted.Two cradle type pressure pieces form acradle type joint.
The cradle type pressure pieces now roll offone another with very little friction as they“drive” the chain within the track radius ofthe taper pulleys.
In this way, lost power and wear areminimized despite the high torque and thelarge angle of bend. The result is longservice life and optimal efficiency.
Cradle TypePressure Piece
SSP 228/027
Taper Pulley of the Variator
Cradle TypePressure Pieces
Top
View
Shackle
Side
View
CradleType Joint
41
Modules
Acoustic Measures
Two different lengths of link plate are usedto ensure that the chain runs as quietlyas possible.
When using a constant length oflink plate, the cradle type pressurepieces strike the taper pulleys at uniformintervals and induce vibrations which causea noise nuisance.
Using different lengths of link platecounteracts resonance and minimizesrunning noise.
SSP 228/028
Different Lengthsof Link Plate
42
Modules
The Oil Supply
In the multitronic®, power transmission isdependent on the electrical power supplyand also on the hydraulics.
In order to work, an electric current and
adequate oil supply are required.
The oil pump is the main power consumerin the transmission and its capacity isimportant for overall efficiency.
The transmission control and coolingsystems are designed to run on a minimumof oil, and an innovative oil supply systemhas been developed.
Intake Filter
The Oil Pump
The oil pump is mounted directly on thehydraulic control module to avoidunnecessary interfaces. The oil pumpand the control module form a compactunit, which reduces pressure losses andproduction costs.
The multitronic® is equipped with anefficient crescent pump. This pumpproduces the necessary pressures, butrequires only a relatively small quantity ofoil. A suction jet pump (entrainment pump)supplies the additional quantity of oilrequired for the clutch cooling at lowpressure. The compact crescent-vanepump is integrated in the hydraulic controlmodule and driven directly by the inputshaft by a spur gear and pump shaft.
SSP 228/034
HydraulicControl Module(Valve Body)
Pressure Tube Routedto Suction Jet Pump(Entrainment Pump)
Oil Pump
43
Modules
As a special feature, the oil pump has axialand radial clearance adjustment.
A pump with good “internal sealing” isrequired in order to produce high pressuresat low engine speeds.
“Internal sealing” refers to theability of the pump to minimizeleakage past the surfaces movingthe fluid through the pump.
SSP 228/035Axial Plates
Conventional oil pumps do not meetthese requirements due to componenttolerances.
The axial clearance between the gearsand the housing, as well as the radialclearance between the gears and thecrescent vane can vary depending on thetolerance zone position of the componentparts in a conventional pump.
The pressure generated can thus more orless escape “internally.”
The result will be a loss of pressure and adrop in efficiency.
Segmental SpringsSealing Roller
Stop PinInner Segment
Spring Rod
Oil Pump Housing
Outer Segment
Driver
44
Modules
Axial Clearance Adjustment
Two axial plates cover the pressure rangeof the crescent pump and form a separatedischarge casing inside the pump.They seal the pump pressure chamberlaterally (axially). These plates, fitted witha special seal, are supported by the oilpump housing or the pump plate of thehydraulic control module.
The axial plates are designed to allow thepump pressure to act between the axialplates and the housing. The seal preventspressure from escaping. As pump pressure
SSP 228/051
increases, the axial plates are pressedmore firmly against the crescent seal andthe pump gears, which compensates foraxial clearance.
The axial and radial clearanceadjustment allows the pump togenerate the required highpressures and simultaneouslyachieve high efficiency despite itscompact design.
Seal
Axial Plate
Oil Pump Housing
Axial Plate
Axial Plate
45
Modules
Radial Clearance Adjustment
The radial clearance adjustment featurecompensates for the radial gap betweenthe crescent seal and the gears (pinion andring gear).
For this purpose, the crescent seal is splitin two segments, the inner segment andthe outer segment.
The inner segment seals the pressurechamber off from the pinion. It also holdsthe outer segment in a radial direction.The outer segment seals the pressurechamber off from the ring gear. The pumppressure flows between the two
SSP 228/049
Inner Segment
segments. The segments are pressedmore firmly against the pinion and ring gearas the pump pressure increases, whichcompensates for radial clearance.
When the pump is depressurized, thesegmental springs provide the basiccontact pressure for the segments and thesealing roller, and improve the suctioncharacteristics of the oil pump.
They also ensure that the pump pressurecan act between the segments and on thesealing roller.
Crescent SealOuter Segment
Pinion
Ring Gear
46
Modules
The Suction Jet Pump
(Entrainment Pump)
The quantity of oil required to ensuresufficient cooling of the two clutchesexceeds the capacity of the internal gearpump, particularly when pulling away(there is high heat buildup due to slip).
SSP 228/036
View of Suction Jet Pump
(Entrainment Pump)
Pressure Tube(Routed toforward clutch)
Inlet Pipe
Pressure Tube(Routed from hydrauliccontrol moduleto suction jet pump(entrainment pump))
ATF Overflow Pipe
A suction jet pump (entrainment pump) isintegrated in the clutch cooling system tosupply the quantity of oil required forcooling the clutch.The suction jet pump (entrainment pump) ismade of plastic and projects deep into theoil sump.
47
Modules
SSP 228/037
Suction Jet Pump (Entrainment Pump)
(Shown in Profile and Folded Out)
CheckValve
VenturiNozzle
This is how it works:
The suction jet pump (entrainment pump)operates according to the Venturi principle.When the clutch requires cooling, thecooling oil (pressurized oil) supplied by theoil pump is ducted through the suction jetpump (entrainment pump) in the formof a powerful jet. The oil flow through theentrainment pump nozzle results in a partialvacuum which “sucks” oil out of the oilsump and, together with the powerful jet,results in a large, almost depressurizedquantity of oil.
The quantity of cooling oil is almostdoubled as required without additionalpumping capacity.A check valve prevents the suction jetpump (entrainment pump) from running dryand facilitates a quick response of thecooling oil feed.
48
Modules
Electro-Hydraulic Control
A new feature is that theoil pump, hydraulic controlmodule (valve body) andTransmission Control ModuleJ217 are combined as acompact assembly.
Selector Shaft
The hydraulic control module containsthe manual selector valve, nine hydraulicvalves and three electromagnetic pressurecontrol valves.
The hydraulic control module and theTransmission Control Module J217 areconnected electrically by direct plug-incontacts.
SSP 228/063
Oil Pump
ManualSelectorValve
Transmission ControlModule J217
Direct Plug-In Contact
Hydraulic Control Module
49
Modules
The hydraulic control module executes thefollowing functions:
• Forward-reverse clutch control
• Clutch pressure regulation
• Clutch cooling
• Pressurized oil supply to the contactpressure control
• Transmission control
• Supplying the splash oil cover
The hydraulic control module isconnected directly to pulley set 1 andpulley set 2 by “screw inserts.”
The screw inserts are sealed by O-rings.
Screw Inserts for Pulley Set 1
SSP 228/085
Screw Inserts for Pulley Set 2
O-Ring
Oil Injection Hole forSplash Oil Cover
O-Ring
50
Modules
Sectional View of Valve Plate
SSP 228/047
The descriptions of the valves that followrefer to valves not included in the previousmodule/function descriptions:
To protect the component parts, pressure
limiting valve 1 limits the pump pressureto maximum 1189 psi (8 200 kPa).
The pressure control valves aresupplied with a constant pilot controlpressure of 73 psi (500 kPa) by thepilot pressure value.
SSP 228/044
Hydraulic Control Module
(Transmission Control Module J217 Removed)
Connection toAutomaticTransmissionSender -1-for HydraulicPressure G193
ElectricalConnectorfor N88
ElectricalConnectorfor N216
ElectricalConnectorfor N215
PressureLimitingValve 1
Connection toAutomaticTransmissionSender -2-for HydraulicPressure G194
Pressure ControlValve -2- forAutomaticTransmissionN216
SolenoidValve 1N88
PilotPressureValve
PressureControl Valve-1- forAutomaticTransmissionN215
ClutchControlValve
MinimumPressureValve
PressureLimitingValve 1Clutch
CoolingValve
The minimum pressure valve preventsthe oil pump drawing in engine air whenthe engine is started. When pump output ishigh, the minimum pressure valve opensand allows oil to flow from the oil returnpipe to the suction side of the oil pump;this improves efficiency.
51
Modules
The pressurizing valve controls thesystem pressure so that sufficient oilpressure is always available for a particularfunction (application of contact pressureor adjustment).
Solenoid Valve 1 N88, Pressure ControlValve -1- for Automatic Transmission N215,and Pressure Control Valve -2- forAutomatic Transmission N216 are designedas “pressure control valves.”
They convert an electric control current to aproportional, hydraulic control pressure.
The Solenoid Valve 1 N88 controls theclutch cooling valve and the safety valve.Pressure Control Valve -1- for AutomaticTransmission N215 actuates the clutchcontrol valve. Pressure Control Valve -2- forAutomatic Transmission N216 actuates thereduction valve.
Sectional View of Pump Plate
ReductionValve
SSP 228/048
SafetyValve
ManualSelectorValve
VolumetricFlow RateLimiting Valve
PressurizingValve
SSP 228/100
Current in mA
SSP 228/101
Diagram of Pressure Control Valve
Con
trol
Pre
ssur
e in
psi
(kP
a)
Pressure Control Valve
(Proportional Valve)
0 (0)0 1000
73 (500)
52
Modules
Selector Shaft and Parking Lock
A mechanical connection (cable pull) fortransmission of selector lever positions P,R, N and D still exists between the gateselector lever and the transmission.
The following functions are executed viaselector shaft:
• Actuation of the manual selector valve inthe hydraulic control module, i.e.hydromechanical control of vehicleoperating state (forward/reverse/neutral).
• Operating the parking lock.
• Actuation of the multi-functional switchfor electronic recognition of the selectorlever position.
SSP 228/065
Actuation ofthe Outer SelectorMechanism
In selector lever position P, the linkagewith locking teeth is displaced axially sothat the parking lock ratchet is pressedagainst the parking lock gear and theparking lock is engaged.
The parking lock gear is permanentlyconnected to the drive pinion.
Parking Lock Ratchet
Linkage with Locking Teeth
Pulley Set 2
Detent Gate
Drive Pinion
Magnetic Gate
Parking Lock Gear
Manual Selector Valve
Selector Shaft
53
Modules
Transmission Housing Ducting
and Sealing Systems
Sheathed Sealing Ring System
The multitronic® is equipped with a newsheathed sealing ring system.
The sheathed sealing rings seal thepressure cylinder and the variable-displacement cylinder of pulley set 1,the pulley set 2, and the piston forthe forward clutch.
The O-ring presses down and seals thesheathed sealing ring.
The oil pressure present assists thesheathed sealing rings with contactpressure application.
Advantages of the sheathed sealing ringsystem:
• Good anti-friction properties
• Low displacement forces
• Wear is minimized
• Stable at high pressures
SSP 228?062
Double-Corrugated Sealing Ring
O-Ring
SheathedSealing Ring
54
Modules
To save weight, the three-piecetransmission housing is manufacturedfrom the AZ91 HP magnesium alloy.This alloy is highly corrosion resistant,easy to process and has a 17.6 lb (8 kg)weight advantage over a conventionalaluminum alloy. As a special feature,the ATF pressurized oil is not distributedthrough housing ducts as is usual onautomatic transmissions, but almostexclusively by pipes.
Axial sealing elements are used to sealthe pipe connections. The axial sealingelements of the pressure pipes have twosealing lips which apply a higher contactpressure as a result of the oil pressure, andtherefore seal the pipes reliably. Diagonalpipe connections can also be sealedwithout difficulty using this technology (e.g.pressure tube connected to reverse clutch).The oil pump intake fitting axial sealingelement has sealing beads which seal thefitting by contact pressure.
The double-corrugated sealing ring (seepage 53) separates the ATF reservoirfrom the final drive oil reservoir. It preventsthe ATF from entering the final drive andoil from the final drive entering theATF reservoir.
Leaks in the double-corrugated sealing ringbecome visible at the oil return hole.
Groove forDouble-CorrugatedSealing Ring
Inner Section
Pressure Tube Routedto Reverse Clutch
Differential PressureValve 1 withATF Strainer 1
Oil Return Hole
55
Modules
Pressure Tube Routed toSuction Jet Pump (Entrainment Pump)
SSP 228/041
Oil Drain Screw
Suction Jet Pump (Entrainment Pump)
ATF Inspection Plug
Axial Sealing Element
Pressure Tube Routed toForward Clutch
ATF Level
Intake Filter
Return Pipe from ATF Coolerwith Spray Nozzles for Chainand Pulley Sets
56
Modules
Hydraulic Circuit Diagram
23
Pulley Set 1
2 Pulley Set 2
7
3
4 5 19
22
2011
26
28
15
18 6
27
24 9
8 30
1410
13
25
31
1
29
12P R N D
21
16
SSP 228/039
32
17
57
Modules
Hydraulic Circuit Diagram Legend
(Selector Lever Position P
and Engine “OFF”)
1 Pressure Limiting Valve 12 Pressure Limiting Valve 23 Differential Pressure Valve 14 Differential Pressure Valve 25 ATF Filter6 Manual Selector Valve7 ATF Cooler8 Clutch Cooling Valve9 Clutch Control Valve
10 Minimum Pressure Valve11 Measuring Point for Contact
Pressure (Registered by G194)12 Measuring Point for Clutch Pressure
(Registered by G193)13 Solenoid Valve 1 N88
(Clutch Cooling/Safety Shut-Off)14 Pressure Control Valve -1- for
Automatic Transmission N215 (Clutch)15 Pressure Control Valve -2- for
Automatic Transmission N216 (Ratio)16 Oil Pump17 Selector Lever Position PRND18 Reverse Clutch19 ATF Strainer 120 ATF Strainer 221 ATF Strainer 322 Four Spray Holes for Pulley Set
Lubrication/Cooling23 ATF Intake Filter24 Safety Valve25 Suction Jet Pump (Entrainment Pump)26 Reduction Valve27 Forward Clutch28 Volumetric Flow Rate Limiting Valve29 Pressurizing Valve30 Pilot Pressure Value31 To Splash Oil Cover32 To the Clutches
Differential Pressure Valve 1and ATF Strainer 1
SSP 228/071
Pressure Limiting Valve 2 inthe Transmission Housing
Return Pipe fromATF Cooler
In the Oil Sump
Hydraulic Control Module
Peripheral Components inthe Vehicle
Volkswagen Technical Site: http://volkswagen.msk.ru http://vwts.ru огромный архив документации по автомобилям Volkswagen
58
Modules
ATF Cooling
The ATF coming from pulley set 1 initiallypasses through the ATF cooler. The ATFflows through the ATF filter before it isreturned to the hydraulic control module.
The ATF cooler is integrated in the radiator.Heat is exchanged with the coolant inthe engine cooling circuit (oil-coolantheat exchanger).
The differential pressure valve 1 protectsthe ATF cooler against excessively highpressures (ATF cold). When the ATFis cold, a large pressure differencedevelops between the supply line and thereturn line. When a specific pressuredifferential is reached, the differentialpressure valve 1 opens and the supply line
is short-circuited with the return line tobypass the ATF cooler. This also causesthe temperature of the ATF to rise tonormal operating temperature rapidly.
The differential pressure valve 2 openswhen the flow resistance of the ATF filter istoo high (e.g. filter blockage). This preventsthe differential pressure valve 1 fromopening and the ATF cooling system frombeing disabled by the backpressure.
If the ATF cooler is leaky, coolantcan enter the ATF. Even smallquantities of coolant in the ATFcan have an adverse effect onclutch control.
SSP 228/090
Peripheral Components in the Vehicle
To HydraulicControl Module
ATF Filter
multitronic®
PressureLimitingValve 2
Supply Line
ATF Cooler
ATF FilterReturn LineDifferential
PressureValve 2
ATF Strainer 1
DifferentialPressureValve 1
FromPulleySet 1
Supply Line
Return Line
59
Control
Transmission Control Module J217
A special feature of multitronic® is theintegration of the electronic TransmissionControl Module J217 in the transmission.
The control module is attached directly tothe hydraulic control module with bolts.
The connection to the three pressureregulating valves is made directly from thecontrol module by means of robust plug-incontacts (gooseneck contacts); there areno wiring connections. A 25-pin compactconnector forms the interface tothe vehicle.
A further new feature is the integration ofsensor technology in the control module.
• Multi-Function TransmissionRange Switch F125
• Sensor for Transmission RPM G182• Sender for Transmission
Output RPM G195• Sender -2- for Transmission
Output RPM G196• Transmission Fluid Temperature
Sensor G93• Automatic Transmission Sender -1-
for Hydraulic Pressure G193(Clutch Pressure)
• Automatic Transmission Sender -2-for Hydraulic Pressure G194(Contact Pressure)
SSP 228/055
Plug-In Contact forSolenoid Valve 1 N88
Transmission ControlModule J217
Sender for Transmission Output RPM G195 andSender -2- for Transmission Output RPM G196
Plug-In Contact for PressureControl Valve -1- for AutomaticTransmission N215
AutomaticTransmissionSender -1- forHydraulicPressure G193(Clutch Pressure)
Multi-FunctionTransmissionRange SwitchF125
Plug-In Contactfor Pressure ControlValve -2- for AutomaticTransmission N216(Concealed by Sensorfor TransmissionRPM G182)
Automatic Transmissionfor Sender -2-Hydraulic Pressure G194(Contact Pressure)
Sensor forTransmissionRPM G182
60
Control
A strong aluminium plate acts as thebase for the electronics and serves todissipate heat. The housing is made ofplastic and securely riveted to the base.It accommodates all the sensors, so neitherwiring nor plug-in contacts are necessary.
Since the majority of electrical failures areattributable to faulty wiring and plug-incontacts, this construction offers a veryhigh degree of reliability.
Sensor for Transmission RPM G182,Sender for Transmission Output RPMG195, Sender -2- for TransmissionOutput RPM G196, and Multi-FunctionTransmission Range Switch F125 are alldesigned as Hall sensors.
SSP 228/077
Hall sensors are free of mechanical wear.Their signal is immune to electromagneticinterference, which improves their reliabilitystill further.
Because there are only a fewinterfaces to the TransmissionControl Module J217, themultitronic® does without aseparate wiring harness.The wiring is integrated in theengine harness.
25-Pin Connector
Transmission FluidTemperature Sensor G93
Sensor forTransmissionRPM G182(One Hall Sensor)
Multi-FunctionTransmission RangeSwitch F125(Four Hall Sensors)Sender for Transmission Output RPM G195
and Sender -2- for Transmission OutputRPM G196 (Two Hall Sensors)
61
Control
Fault Indication
Faults in the multitronic® are registeredby the self-diagnosis function. Faults areindicated to the driver on the selector leverposition indicator in the instrument clusterbased on their effect on multitronic®operation or on driving safety. In this case,the selector lever position indicator alsoserves as a fault indicator.
Faults are registered by the multitronic®
three different ways:
1. The fault is stored and a substituteprogram enables continued operationof the vehicle with some restrictions.This state is not indicated to the driver,since it is not critical with regard todriving safety or multitronic® operation.The driver may notice the fault by theway the vehicle handles and seek theassistance of an Audi dealer.
2. The fault is stored and a substituteprogram enables continued operationof the vehicle with some restrictions.The selector lever position indicatoralso indicates the presence of a faultby inverting the display. The situationis still not critical for driving safety or formultitronic® operation. However, thedriver should take the vehicle to an Audidealer as soon as possible to have thefault rectified.
SSP 228/102
SSP 228/103
62
Control
3. The fault is stored and a substituteprogram enables continued operation ofthe vehicle with some restrictions, atleast until it stops. The selector leverposition indicator indicates the presenceof a fault by flashing. This state iscritical with regard to driving safety ormultitronic® operation. Therefore, thedriver is advised to take the vehicle to anAudi dealer immediately to have the faultrectified.
In some cases when thedisplay is flashing, vehicleoperation will only bemaintained until the nexttime the vehicle stops.The vehicle can subsequentlyno longer be driven! In othercases, vehicle operationcan be resumed by restartingthe vehicle.
SSP 228/104
63
Control
Sender for Transmission OutputRPM G195 and Sender -2- forTransmission Output RPM G196
Sensors
The signals generated by the sensors cannot be measured with conventionalequipment because the control module isintegrated into the transmission. A checkcan only be performed with the VehicleDiagnosis, Test and Information SystemVAS 5051 using the following functions:
• 02 — Interrogate fault memory
• 08 — Read measured value block
This Self-Study Program does not describethe sensor signals in detail.
If a sensor fails, the Transmission ControlModule J217 generates substitute valuesfrom the signals of other sensors as wellas the information from the networkedcontrol modules. Vehicle operation canthus be maintained.
The effects on vehicle performance areso small that the driver may not noticethe failure of a sensor immediately.An additional fault can, however, haveserious effects.
The sensors are an integral partof the Transmission ControlModule J217. If a sensor fails,the entire control module mustbe replaced.
Sensor for Transmission RPM G182,
Sender for Transmission Output RPM G195, and
Sender -2- for Transmission Output RPM G196
SSP 228/078
Sender Wheelfor G182Sender Wheel for
G195 and G196
Sensor forTransmissionRPM G182
64
Control
Sensor for Transmission RPM G182
registers the rotation speed of pulley set 1and therefore represents the actualtransmission input speed.
Transmission input speed...
... is used together with engine speedfor clutch control (for more detailedinformation, refer to “The Micro-SlipControl,” page 21).
... serves as the reference input variable fortransmission control (for more detailedinformation, refer to “The TransmissionControl,” page 30).
Effects of failure of Sensor for
Transmission RPM G182:
• The clutch engagement is controlledaccording to fixed parameters.
• The micro-slip control and the clutchadaptation function are deactivated.
Engine speed is used as a substitute value.
Fault indication: none
Sender for Transmission Output RPM
G195 and Sender -2- for Transmission
Output RPM G196 register the rotationspeed of pulley set 2 and with it thetransmission output speed.
The signal from Sender for TransmissionOutput RPM G195 is used for registeringrotation speed. The signal from Sender -2-for Transmission Output RPM G196 is usedfor recognition of direction of rotation andtherefore also for distinguishing betweenforward travel and reverse travel (refer to“Clutch Control when Vehicle Is Stationary(Slip Control),” page 19).
“Transmission output speed” is used...
... for transmission control,
... for slip control,
... for the hill-holder function,
... for determining the road speed signal forthe instrument cluster.
If the Sender for Transmission Output RPMG195 fails, the transmission output speedis determined from the signal fromSender -2- for Transmission Output RPMG196. The hill-holder function isdeactivated also.
If Sender -2- for Transmission Output RPMG196 fails, the hill-holder function isdeactivated.
If both senders fail, a substitute value isgenerated from the information availableon wheel speeds across the CAN bus.The hill-holder function is deactivated.
Fault indication: none
Sender Wheels
A magnetic ring with a row of magnetsis located on the end face of each senderwheel; the magnets act as north/southpoles.
• Sender wheel for Sensor forTransmission RPM G182has 40 magnets.
• Sender wheel for Sender forTransmission Output RPM G195 andSender -2- for Transmission OutputRPM G196 has 32 magnets.
Heavy contamination of themagnetic ring from metal swarfcaused by wear can impair theperformance of these senders.Therefore, metal swarfadhering to the magnetic ringshould be removed beforeperforming other repairs.
65
Control
Sender Wheel
SSP 228/109
N S N S N
Signal from Sender forTransmission Output RPM G195
1st Phase = 100%
25%
Sender -2- forTransmissionOutput RPM G196
Sender forTransmissionOutput RPM G195
How the Direction
of Rotation Is Registered:
A magnetic ring comprising a row of 32individual magnets (north/south poles) islocated on the end face of the senderwheel for Sender for Transmission OutputRPM G195 and Sender -2- for TransmissionOutput RPM G196.
The position of Sender for TransmissionOutput RPM G195 relative to Sender -2-for Transmission Output RPM G196 isoffset so that the phase angles of thesender signals are 25% out of phasewith one another.
The direction of rotationis registered for thehill-holder function.
After ignition “ON,” the control moduleobserves the falling edges of the signalsfrom the two senders and records thelevels of the other senders.
As shown in the example, the level ofSender -2- for Transmission Output RPMG196 is “low” at the falling edge of the
signal from Sender for Transmission OutputRPM G195, and the level of Sender forTransmission Output RPM G195 is “high”at the falling edge of the signal from Sender-2- for Transmission Output RPM G196.The Transmission Control Module J217interprets this “pattern” as forward travel.
SSP 228/110
Forward Travel
High
Low
High
Low
Sender forTransmissionOutput RPMG195
Sender -2- forTransmissionOutput RPMG196
Direction of Rotationof Sender Wheel
66
Control
Reverse Travel
Direction of Rotationof Sender Wheel
SSP 228/111
Low
High
Low
High
In this example, the level of Sender -2- forTransmission Output RPM G196 is “high”at the falling edge of the signal from Senderfor Transmission Output RPM G195 and thelevel of Sender for Transmission Output
RPM G195 is “low” at the falling edge ofthe signal from Sender -2- for TransmissionOutput RPM G196. The TransmissionControl Module J217 interprets this“pattern” as reverse travel.
67
Sender forTransmissionOutput RPMG195
Sender -2- forTransmissionOutput RPMG196
Control
68
Control
Automatic Transmission Sender -1- for
Hydraulic Pressure G193
Automatic Transmission Sender -1- forHydraulic Pressure G193 registers theclutch pressure of the forward- andreverse-gear clutches and is used formonitoring the clutch function(see “The Clutch Control,” page 15).
Clutch pressure monitoring has a highpriority, so malfunctioning of AutomaticTransmission Sender -1- for HydraulicPressure G193 usually causes the safetyvalve to be activated (see “Safety Shut-Off,” page 18).
Fault indication: flashing
Automatic Transmission Sender -2- for
Hydraulic Pressure G194
Automatic Transmission Sender -2- forHydraulic Pressure G194 registers thecontact pressure, which is regulated by thetorque sensor. As the contact pressure isalways proportional to the actualtransmission input torque, the transmissioninput torque can be calculated veryaccurately using Automatic TransmissionSender -2- for Hydraulic Pressure G194.
The signal from Automatic TransmissionSender -2- for Hydraulic Pressure G194 isused for clutch control (control andadaptation of the slip function).If Automatic Transmission Sender -2- forHydraulic Pressure G194 malfunctions, theslip control adaptation function isdeactivated. The slip torque is thencontrolled by means of stored values.
Fault indication: none
SSP 228/093
Automatic Transmission Sender -1-for Hydraulic Pressure G193
SSP 228/094
Automatic Transmission Sender -2- forHydraulic Pressure G194
69
Control
Multi-Function Transmission
Range Switch F125
Multi-Function Transmission Range SwitchF125 has four Hall sensors which arecontrolled by the magnetic gate on theselector shaft. The signals from the Hallsensors are interpreted in the same way asthe positions of mechanical switches.A high level means: switch is closed (1).A low level means: switch is open (0).Therefore, a Hall sensor “switch”generates two signals: “1” and “0.”
Sixteen different gearshift combinationscan be generated with four Hall sensors:
• four gearshift combinations for therecognition of selector lever positionsP, R, N, D,
• two gearshift combinations which areregistered as intermediate positions(P-R, R-N-D),
• ten gearshift combinations which arediagnosed as being faulty.
SSP 228/095
Four HallSensors(A, B, C, D)
Selector Shaft
Magnetic Gate
70
Control
Gearshift Combinations
Example:
The selector lever is located in selectorlever position “N.” If Hall sensor “C”for example fails, gearshift combination“0 0 0 1” will be implemented.The Transmission Control Module J217can no longer identify selector leverposition “N.” It recognizes the gearshiftcombination as being faulty and initiatesthe appropriate substitute program.
If Hall sensor “D” fails, itwill no longer be possible tostart the engine.
The Transmission Control Module J217requires the information on selector leverposition for the following functions:
• Starter inhibitor control• Backup light control• Park/Neutral interlock control• Information on the vehicle operating
state (forward/reverse/neutral) forclutch control
• Lock ratio when reversing
Different faults in Multi-FunctionTransmission Range Switch F125manifest themselves very differently.Pulling away may not be permitted incertain circumstances.
Fault indication: flashing
For a table of gearshift combinations, please refer to the Repair Manual!
srosneSllaHA B C D
noitisoPreveLrotceleS snoitanibmoCtfihsraeGP 0 1 0 1
R-PneewteB 0 1 0 0R 0 1 1 0
N-RneewteB 0 0 1 0N 0 0 1 1
D-NneewteB 0 0 1 0D 1 0 1 0
tluaF 0 0 0 0tluaF 0 0 0 1tluaF 0 1 1 1tluaF 1 0 0 0tluaF 1 0 0 1tluaF 1 0 1 1tluaF 1 1 0 0tluaF 1 1 0 1tluaF 1 1 1 0tluaF 1 1 1 1
71
Control
Transmission Fluid Temperature
Sensor G93
Transmission Fluid Temperature SenderG93 is integrated into the electronics ofthe Transmission Control Module J217.It records the temperature of theTransmission Control Module J217aluminum mounting which is a closeapproximation of the transmissionoil temperature.
Transmission oil temperature influencesboth clutch control and transmission inputspeed control. Therefore, it plays animportant role in the control andadaptation functions.
If Transmission Fluid Temperature SenderG93 fails, the engine temperature is usedto calculate a substitute value. Adaptationfunctions and certain control functionsare deactivated.
Fault indication: inverted
Transmission ControlModule J217
To protect the component parts of thetransmission, engine performance isreduced if the transmission oil temperatureexceeds approximately 293°F (145°C).
If the transmission oil temperaturecontinues to increase, engine performanceis reduced more and more (if necessary,until the engine is running at idling speed).
Fault indication: flashing
“Brake Actuated” Signal
The “Brake actuated” signal is required forthe following functions:
• For the function of the gear selectorlever shift lock
• For slip control• For the dynamic control program (DCP)
There is no direct interface to the VacuumVent Valve, Brake F47. The “Brake actuated”signal is provided by the Motronic EngineControl Module J220 across the CAN bus.
SSP 228/107
Motronic Engine Control Module J220
Shift Lock Solenoid N110 inthe Selector Lever BracketCombined Brake
Light Switch F andVacuum Vent Valve,Brake F47
CAN
100 %0
5.0
20 % 40 % 60 % 80 %
72
Control
SSP 228/106
KickdownRange
AcceleratorPedal Limit Stop
MechanicalFull-Throttle Stop
Driver Torque Input
Sig
nal V
olta
ge in
V
Accelerator Pedal Travel
Sender -2- forAccelerator PedalPosition G185
Sender -1- forAcceleratorPedal PositionG79
“Kickdown” Information
A separate switch is not used for thekickdown information.
A spring-loaded pressure element locatedon the accelerator pedal module creates a“point of resistance” conveying a“kickdown feel” to the driver.
When the driver activates the kickdownfunction, the full-throttle voltage value ofSenders -1- and -2- for Accelerator Pedal
Position G79 and G185 in the acceleratorpedal module is exceeded. When a definedvoltage value corresponding to thekickdown point is exceeded, the MotronicEngine Control Module J220 sendskickdown information to the TransmissionControl Module J217 across theCAN bus.
73
Control
TransmissionControl Module J217
SSP 228/108
CAN
Motronic EngineControl Module J220
Accelerator Pedal Module(Contains Sender -1- for AcceleratorPedal Position G79 and Sender -2- forAccelerator Pedal Position G185)
In automatic mode, the most sporty controlcharacteristic for maximum acceleration isselected when the kickdown functionis activated.
The kickdown function does not have to becontinuously activated. After the kickdownfunction has been activated once, theaccelerator pedal need only be held in thefull-throttle position.
If the accelerator pedal moduleis replaced, the kickdown shiftpoint must be calibrated usingthe Diagnosis, Testing andInformation System VAS 5051(refer to Repair Manual).
+ -
P
R N D
Tiptronic Switch F189
Tiptronic Switch F189 is integrated onthe printed circuit board of the gear changemechanism. It has three Hall sensors whichare actuated by a magnet located onthe shutter.
A - Sensor for downshift
B - Sensor for Tiptronic recognition
C - Sensor for upshift
Seven LEDs are located on the printedcircuit board: one for each selector leverposition, one for the “Brake actuated”symbol, and one each for the + and –symbols on the Tiptronic gate.
Four Hall Sensors for Selector Lever Position
SSP 228/079
Each selector lever position LED iscontrolled by a separate Hall sensor.
The switches of Tiptronic Switch F189apply ground (low signal) to theTransmission Control Module J217 whenactuated. If a fault occurs, the Tiptronicfunction is disabled.
Fault indication: inverted
LED
Tiptronic SwitchF189 with ThreeHall Sensors (C, B, A)
Selector Lever Gate
Printed Circuit Boardfor Selector Lever Gate
Solenoid forHall Sensors
Control
74
Control
75
CAN Information Exchange on
multitronic®
In the multitronic® information isexchanged between the TransmissionControl Module J217 and the networkedcontrol modules, apart from only a fewinterfaces, across the drivetrain CAN bus.
The system overview shows informationwhich is supplied by the TransmissionControl Module J217 across the CAN busand received and used by the networkedcontrol modules.
Information Sent bythe Transmission ControlModule J217.
Information Received andEvaluated by the TransmissionControl Module J217.
Driv
etra
in C
AN
Bus
Hig
h
Driv
etra
in C
AN
Bus
Low
Transmission Control Module J217
Specified Engine Torque
Specified Idling Speed
Enable Adaptation —Idling Speed Charge Regulation
Overrun Shut-Off Support
Clutch Protection
Clutch Status
Clutch Torque
Gearshift Operation Active/Inactive
Compressor Switch Off
Selector Lever Position/Drive Position
Vehicle Road Speed
Shift Indicator
Currently Engaged Gear orTarget Gear
Coding in the Motronic EngineControl Module J220
Emergency Running Program(Information on Self-Diagnosis)
On-Board Diagnosis Status
Motronic Engine
Control Module J220
Engine Speed
Specified Idling Speed
Actual Engine Torque
Coolant Temperature
Kickdown Information
Accelerator Pedal Position
Brake Light Switch
Vacuum Vent Valve, Brake
Intake Air Temperature
CCS Status
CCS Specified Road Speed
Altitude Information
Air Conditioner Compressor Status
Emergency Running Program(Information on Self-Diagnosis)
ABS Control Module with
EDL/ASR/ESP J104
ASR Request
EBC Request
ABS Application
EDL Intervention
ESP Intervention
Wheel Speed, Front Left
Wheel Speed, Front Right
Wheel Speed, Rear Left
Wheel Speed, Rear Right
Control
Auxiliary Signals/Interface
The multitronic® provides in addition thefollowing interfaces for informationexchange by CAN bus:
Pin 15 Signal for engine speed
Pin 6 Signal for shift indicator
Pin 5 Signal for road speed
Pin 2 Diagnosis andprogramming interface
Pin 13 Signal for Tiptronic (recognition)
Pin 12 Signal for Tiptronic (downshift)
Pin 14 Signal for Tiptronic (upshift)
Signal for Engine Speed
Engine speed is a key parameter for themultitronic®. To increase the reliabilityof the multitronic®, the information onengine speed is transmitted to theTransmission Control Module J217 by aseparate interface and in addition(redundantly) across the CAN bus (see“Functional Diagram,” page 80).
In the event of faults or if the separate“engine speed signal” interface fails, theinformation on engine speed is adopted bythe CAN bus as a substitute value.
In the event of faults at the “engine speedsignal” interface, the micro-slip controlfunction is deactivated.
76
77
Control
Signal for Shift Indicator
The signal for shift indicator is asquare-wave signal generated by theTransmission Control Module J217 with a20-millisecond constant high level andvariable low level.
Each selector lever position or each“gear” in the Tiptronic function is assignedto a defined low-level duration.
The selector lever position indicator or theshift indicator in the instrument clusterrecognizes by the low-level duration whatselector lever position or what gear isselected and indicates this accordingly.
SSP 228/118Selector Lever Position D
Signal for Shift Indicator on multitronic® — P, R, N, DTrigger Line
Test InstrumentsDSO
Auto Mode
50 ms/Division
T SelectorLeverPosition P
Selector Lever Position R Selector Lever Position N
5 V
/Div
isio
n
78
Control
To simplify the representation, the signalsfrom all six gears for the Tiptronic functionare shown combined in a single diagram.
Signal for Shift Indicator on Tiptronic —
1st, 2nd, 3rd, 4th, 5th and 6th Gear
SSP 228/117
Trigger Line
Test InstrumentsDSO
Auto Mode
50 ms/Division
T
1st 2nd 3rd 4th 5th 6th
Gear5 V
/Div
isio
n
79
Control
Signal for Road Speed
The signal for road speed is a square-wavesignal generated by the TransmissionControl Module J217. The duty cycle isapproximately 50% and the frequencychanges synchronous to road speed.
Eight signals are generated per wheelrevolution and relayed to the instrumentcluster through a separate interface.
The signal is used here for speedometeroperation and is passed on to thenetworked control modules/systems(e.g. engine, air conditioning system, audiosystem, etc.) by the instrument cluster.
1
7
2 3 4 5 6
V
Z
+-
U
U
U
YXW
31 31
ϑ
PRND
+
–
P P
80
Control
Functional Diagram
SSP 228/030Color Codes
= Input Signal
= Output Signal
= Positive
= Ground
= Bidirectional
= Drivetrain CAN Bus
multitronic®
Terminal 15
J226
Terminal 30
N110
SS
F
N88 N216 N215
N182 G195 G196 F125
J217G194 G193 G93
F189
81
Control
Connections and Auxiliary Signals
U To Tiptronic Steering Wheel (Option)V From Terminal 58dW To the Backup LightsX From Ignition Switch Terminal 50Y To Starter Terminal 50Z To the Brake Lights
1 Drivetrain CAN Bus Low2 Drivetrain CAN Bus High3 Signal for Shift Indicator4 Signal for Road Speed5 Signal for Engine Speed6 K-Diagnostic Connection7 Installed in the Hydraulic
Control Module
Because there are onlya few interfaces to theTransmission Control ModuleJ217, the multitronic®does without a separatewiring harness. The wiringis integrated in theengine harness.
Components
F Brake Light SwitchF125 Multi-Function Transmission Range
SwitchF189 Tiptronic Switch
G93 Transmission Fluid TemperatureSensor
G182 Sensor for Transmission RPMG193 Automatic Transmission Sender -1-
for Hydraulic PressureG194 Automatic Transmission Sender -2-
for Hydraulic PressureG195 Sender for Transmission Output
RPMG196 Sender -2- for Transmission
Output RPM
J217 Transmission Control ModuleJ226 Park/Neutral Position Relay
N88 Solenoid Valve 1N110 Shift Lock SolenoidN215 Pressure Control Valve -1-
for Automatic TransmissionN216 Pressure Control Valve -2-
for Automatic Transmission
S Fuse
Volkswagen Technical Site: http://volkswagen.msk.ru http://vwts.ru огромный архив документации по автомобилям Volkswagen
82
Control
Dynamic Control Program
The Transmission Control Module J217 hasa dynamic control program for calculatingthe target transmission input speed.
It is a further development of the dynamicshift program (DSP) already being used inthe CVT.
The object of the dynamic control programis to set the gear ratio so performancematches the driver input as closely aspossible. The driving feel should be likedriving in manual mode.
ResultActual Transmission Input Speed
(and Hence Engine Speed)
Transmission Control
Influencing Factors(e.g. Engine Warmup)
Calculation of Target Transmission Input Speed (Pulley Set 1, Sensor for Transmission RPM G182)
Evaluation of Road Speed andRoad Speed Changes
(Sender for TransmissionOutput RPM G195)
Evaluation of Signals from theAccelerator Pedal Module
Actuation Rate and Position ofAccelerator Pedal
Evaluation of Road Speed andRoad Speed Changes
(Sender for TransmissionOutput RPM G195)
Driver Input
EconomicalSporty
Vertical Section of Route
UphillDownhill
Level
Vehicle Operating State
AccelerationDeceleration
Constant Speed
83
Control
For this purpose the system determinesthe driver's behavior, the vehicle operatingstate and the vertical section of the routeso it can provide the optimum gear ratio inany driving situation.
The Transmission Control Module J217evaluates the actuation rate and angularposition of the accelerator pedal (driverinput), as well as the road speed andvehicle acceleration (vehicle operatingstate), and whether the vehicle is movingup or down a hill or on a level road(vertical section of route).
Using logical combinations of thisinformation, the target level fortransmission input speed is set byvarying the transmission ratio to matchvehicle performance as closely as possibleto driver input. These target levels arerestricted by transmission input rpm limitsand by the performance range parametersfrom most economical to most sporty.They must also account for the verticalsection of the route traveled.
The logical combinations and calculations(control strategy/control philosophy) aredefined by the software and cannotaccount for every eventuality. Therefore,there are still situations in which manualintervention using the Tiptronic functionis called for.
Control strategy varies by vehiclemodel, engine displacement, andcontrol module design.
Vertical Section of Route
UphillDownhill
Level
Vehicle Operating State
AccelerationDeceleration
Constant Speed
Driver Input
EconomicalSporty
84
Control
Dynamic Control Program
Control Strategy
The following examples show controlstrategy during typical driving situations.
Illustration SSP 228/119 shows the speedcharacteristics when accelerating at fullthrottle with the kickdown activated.
By activating the kickdown, the driversignals to the Transmission ControlModule J217 that maximum accelerationis required.
To achieve this, the engine's maximumpower output must be provided quickly.For this purpose engine speed is adjustedfor maximum performance and maintaineduntil the accelerator pedal angle is reduced.
Although the driver will be required toadjust to this unusual behavior, it makesit possible for the vehicle to acceleratewith the maximum possible dynamism.In addition, the vehicle's top speed as afunction of rolling resistance is kept at themaximum possible value.
The fact that the engine speed increasesquickly but the engine does not accelerateto the same extent results in what isknown as the “rubber band effect” or whatfeels like a “slipping clutch.” This effect isalleviated by “intercepting” the increase inengine speed shortly before maximumengine speed is attained.
Kickdown
Acceleration
SSP 228/119
Time
100
80
60
40
20
0
6000
5000
4000
3000
2000
1000
124 (200)
93 (150)
62 (100)
31 (50)
0 (0)
Engine SpeedRPM
Accelerator PedalPosition in%
Road Speedin mph (km/h)
85
Control
To contain this effect, “normal”accelerationat full throttle (without kickdown), as wellas acceleration with lesser acceleratorpedal angles, are characterized by thespeed characteristics shown in illustrationsSSP 228/124 and SSP 228/122.
The “engine speed tracking” function isused for this purpose. Engine speed isregulated depending on the position andactuation rate of the accelerator pedal so
Full Throttle
Acceleration
engine speed increases directlyproportional to road speed.
This control strategy simulates theperformance of multi-step transmissionsand closely matches the driving feel whichthe driver is accustomed to. In keeping withdriving style, the engine rpm level is high(sporty) at large accelerator pedal anglesand low (economical) at small acceleratorpedal angles.
SSP 228/122
Part Throttle
Acceleration,
Throttle 80%
Open
SSP 228/124
Time
Time
1006000
5000
4000
3000
2000
1000
124 (200)
93 (150)
62 (100)
31 (50)
0 (0)
80
60
40
20
0
100
80
60
40
20
0
6000
5000
4000
3000
2000
1000
124 (200)
93 (150)
62 (100)
31 (50)
0 (0)
Engine SpeedRPM
Accelerator PedalPosition in%
Road Speedin mph (km/h)
86
Control
As shown in illustration SSP 228/123,quick changes in accelerator pedalposition are converted to instantaneouschanges in engine speed in order to meetthe driver's demands for performanceor acceleration.
If the driver adopts an economical drivingstyle, as characterized by small acceleratorpedal angles and a slow rate of openingof the throttle, then road speed is increasedat the lowest engine rpm levels (seeillustration SSP 228/121).
Engine Speed
Response to
Quick Changes
in Accelerator
Pedal Angle
Time
Time
SSP 228/123
SSP 228/121
Acceleration in
an Economical
Driving Mode
100
80
60
40
20
0
6000
5000
4000
3000
2000
1000
124 (200)
93 (150)
62 (100)
31 (50)
0 (0)
100
80
60
40
20
0
6000
5000
4000
3000
2000
1000
124 (200)
93 (150)
62 (100)
31 (50)
0 (0)
Engine SpeedRPM
Accelerator PedalPosition in%
Road Speedin mph (km/h)
87
Control
In general, the system responds to areduction in the accelerator pedal angle byreducing the engine rpm level as shown inillustrations SSP 228/120 and SSP 228/123.
If the accelerator is suddenly released,particularly in a sporty driving mode, theengine speed is “held” at a higher levelfor longer.
Acceleration
with Reduced
Accelerator
Pedal Angle
By increasing the braking effect of theengine (high overrun speed), this controlstrategy helps to brake the vehicle andincreases engine dynamism for instantaccelerator response.
In addition, unnecessary transmission ratioadjustments are suppressed.
SSP 228/120
Time
Engine SpeedRPM
Accelerator PedalPosition in%
Road Speedin mph (km/h)
100
80
60
40
20
0
6000
5000
4000
3000
2000
1000
124 (200)
93 (150)
62 (100)
31 (50)
0 (0)
88
Control
Uphill Grade
Higher power demand may be due to anuphill grade or a trailer.
In this case, the engine speed andoutput level must be increased through ashorter ratio without the driver constantlyhaving to open the throttle more as shownin illustration SSP 228/091.
In practice the driver will perceive thiscontrol strategy, known as “loadcompensation,” as a comfort increase.
Motion Resistance
“Power in relation to load” is calculatedin order to detect motion resistance(uphill grade, downhill grade, vehicleoperation with trailer in tow).
It indicates whether power demand ishigher or lower compared to the rollingresistance during vehicle operation on alevel surface (unladen).
PEngine load = Power in relation to load
Pmot = Actual engine output
Pa = Acceleration work
PFW = Power in relation tomotion resistance
Increase in Engine Speed on a Uphill Grade
SSP 228/091
Eng
ine
Spe
ed
Road Speed
Increase inEngine Speed on a5% Uphill Grade
Characteristicwithout Grade
15%Grade
5%Grade
PEngine load = Pmot - Pa - PFW
89
Control
Increase in Engine Speed when Driving Downhill
Driving Downhill
On a downhill grade the situation is slightlydifferent. If the driver wants to be assistedby engine brake effect when drivingdownhill, he must indicate this by pressingthe brake pedal (signal from combinedBrake Light Switch F and Vacuum VentValve, Brake F47).
If the engine is in the overrun phaseand road speed increases even thoughthe brake pedal is pressed, thetransmission ratio is adjusted towardsthe starting torque ratio and with itthe engine braking force is increased.
If the brake pedal is pressed several times(without reduction in road speed), theTransmission Control Module J217gradually adjusts the transmission ratiotowards the starting torque ratio (seeillustration SSP 228/097). Thus the driverhas a great deal of control over the intensityof the engine brake effect.
If the downhill slope decreases, thetransmission ratio is again adjustedtowards the end torque multipliction ratio(overdrive) and the vehicle's road speedincreases slightly.
If the driver enters a downhillgrade pressing the brake pedal(and holds the brake pedaldown), the “downhill function”as described will not be activeinitially. If the road speed is keptalmost constant in this case byapplying the brake, themultitronic® will be unable torecognize the driver's intentionsand therefore cannot assist thedriver by increasing the enginebrake effect. However, if thevehicle exceeds a defined rateof acceleration, the “downhillfunction” will be activatedautomatically.
Engine braking force can becontrolled individually by usingthe Tiptronic function.
SSP 228/097
Press Brake Twice —Engine SpeedIncreases Further,Higher Utilization ofEngine Brake Force
Time
Press BrakeOnce —Engine SpeedIncreases,Engine BrakeEffect Increases
Eng
ine
Spe
ed
90
Control
Driving with Cruise Control
System (CCS)
In overrun mode, the engine brake effect isinsufficient when driving downhill with thecruise control system (CCS) turned onbecause the transmission ratio is often low.
In this case, the engine brake effect isincreased by raising the target transmissioninput speed (transmission control isadjusted towards the starting torque ratio.)
The CCS set road speed is always slightlyhigher than the actual road speed. This isdue to the control tolerance of the CCS andthe safety requirement that the enginemust be in overrun mode.
A maximum overrun speed whichserves as a limit value for transmissioninput speed control is stored in theTransmission Control Module J217.When the maximum overrun speed isreached, the transmission ratio is notadjusted further towards the startingtorque ratio and therefore is limited.
If the engine brake effect is insufficient atmaximum overrun speed, the vehicle'sroad speed increases and the driver has toapply the brakes.
The Tiptronic Function
As mentioned previously, six “gears” canbe selected manually in Tiptronic mode.In this mode, defined transmission ratiosare set and “gears” are simulated(see also page 4).
The performance and shift strategies areidentical to the multi-step transmission withTiptronic (mandatory upshift or mandatorydownshift).
If the Tiptronic function is selected whiledriving, transmission output is stabilized atits current ratio for a seamless transition.The first driver action to select a “gear”will result in a shortened step up or downto one of the six preset Tiptronic ratios.The defined transmission ratios are thenset step by step by shifting up or down.
Reason:
Because the transmission ratio could bebetween two “gears” at the point ofchange-over to Tiptronic mode, animmediate change into a defined ratiocould lead an abrupt change in roadspeed depending on the difference inratio to the next “gear.”
91
Service
Towing
To make towing possible, design measureshave been implemented in the Variator (see“The Variator,” page 27 for details).
When towing a vehicle with multitronic®,the following conditions must be fulfilled:
• The selector lever must inthe “N” position.
• The vehicle's road speed must
not exceed 30 mph (50 km/h).
• Vehicles must not be towed furtherthan 30 miles (50 km).
When towing the vehicle,the oil pump is not driven androtating parts are not lubricated.
Care should therefore betaken in meeting the above-specified conditions since thetransmission may otherwisebe damaged severely.
It is not possible to start thevehicle by towing.
92
Service
Special Tools
The following special tools will be requiredby the service department.
Transmission Lift Hook
T40013
Test Box
V.A.G. 1598/21
Oil Seal Extractor
T40014
SSP 228/125
SSP 228/067
12
34
567
89 10 11 1213 14 15 16 17 1819 20 21 22 23 2425
SSP 228/066
Seal Installer
T40015
93
Service
SSP 228/070
ATF Filler System
VAS 5162
SSP 228/069
Adjustment Plate
3282/30
SSP 228/068
Notes
94
Knowledge Assessment
iii
An on-line Knowledge Assessment (exam) is available for this SSP.
The Knowledge Assessment may or may not be required for Certification.
You can find this Knowledge Assessment at:
www.accessaudi.com
From the accessaudi.com homepage:
Click on the “ACADEMY” Tab –
Click on the “Academy Site” Link –
Click on the ”CRC Certification” Link –
For assistance, please call:
Audi Academy
Learning Management Center Headquarters
1-877-AUDI-LMC (283-4562)
(8:00 a.m. to 8:00 p.m. EST)
Knowledge Assessment