Diagnostico y Troubleshooting

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Service Training

SERV3151

October 2002

TECHNICAL PRESENTATION

APPLIED DIAGNOSTICS AND

TROUBLESHOOTING

INTRODUCTION


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APPLIED DIAGNOSTICS ANDTROUBLESHOOTINGINTRODUCTION

AUDIENCE

Service training instructors and dealer service technicians.

CONTENT

This presentation discusses a diagnostic and troubleshooting process for repairing machine faults.

OBJECTIVES

After learning the information in this presentation, the student will be able to:

1. identify the skills required to perform effective diagnostics;

2. recognize the basic troubleshooting strategies commonly used to diagnose machine faults;

3. identify and explain the troubleshooting process flow chart steps;4. demonstrate use of the troubleshooting process while diagnosing a machine fault; and

5. evaluate the effectiveness of the troubleshooting process used after a fault has been diagnosed and

repaired.

REFERENCES

"Troubleshooting the Troubleshooting Course" by Robert F. Mager (ISBN-1-879618-09-5)

PREREQUISITES

None

HOW TO USE THE APPLIED DIAGNOSTICS AND TROUBLESHOOTING

This module is the cornerstone segment of the diagnostic and troubleshooting modules found on

"Service Fundamentals"--SERV3100. The module is intended to form the basis upon which the other

modules are built. The diagnostic processes found in this module are to be applied to all other system

specific modules to form a consistent diagnostic process that can be taught to field technicians looking

to improve their diagnostic ability. The following modules consist of a brief review of the diagnostic

process followed by system specific case studies designed to allow the technician to fully develop their

diagnostic skills.

Estimated Time: 2 Hours

Visuals: 19

Serviceman Handouts:

Form: SERV3151

Date: 10/02

2002 Caterpillar Inc.


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TABLE OF CONTENTS

INTRODUCTION ..................................................................................................................5

CLASS EXERCISE 1.............................................................................................................6

CLASS EXERCISE 2.............................................................................................................8

TROUBLESHOOTING TRAITS.........................................................................................10

CLASS EXERCISE 3 ...........................................................................................................11

TROUBLESHOOTING STRATEGIES ...............................................................................13

CLASS EXERCISE 4...........................................................................................................16

TROUBLESHOOTING PROCESS .....................................................................................18

CASE STUDY......................................................................................................................29

CONCLUSION.....................................................................................................................30

VISUALS LIST ....................................................................................................................31

SERVICEMAN'S HANDOUTS...........................................................................................32

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INSTRUCTOR NOTES

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1

INTRODUCTION

This presentation discusses the basics of troubleshooting and diagnostic

principals to help repair machine faults. To repair a machine quickly and

properly it is important to use a systematic approach.

An effective troubleshooting and diagnostic process will reduce

unnecessary parts replacement, lost time on unnecessary diagnostic

procedures, and customer dissatisfaction from faulty or incomplete

repairs.

Teaching troubleshooting can be a difficult task because each technician

learns differently and all technicians are not at the same level. However,

with a logical process, all technicians can improve their diagnostic

capabilities.

Critical thinking skills can be taught through logical processes andprocedures. The basic procedures must be followed deliberately and

repeatedly until they can be visualized and put into a mental picture.

INSTRUCTOR NOTE: In general, diagnostics and troubleshooting

are defined as "a logical problem solving process to rapidly and

efficiently achieve a solution to a problem." The terms diagnostics

and troubleshooting will be used interchangeably throughout this

presentation.

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2002 Caterpillar Inc.


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2

CLASS EXERCISE 1

The following exercise will challenge the student's critical thinking skills:

Objective: Remove the washer from the bolt.

The nut is welded to the bolt and the washer will not quite slip over the

shank.

INSTRUCTOR NOTE: Encourage the students to think beyond the

obvious.

Courtesy of Marty Cirbo, Wagner Equipment Co., Denver, Colorado.

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3

Things are not always as they appear to be. The nut can be removed from

the bolt, but a visual inspection does not reveal the solution.

Technicians who can think in non-traditional ways will arrive at the root

cause of the problem.

Real World Situation:

A prototype engine on a dynamometer was burning oil whenever it was

off idle. The following components were replaced:

Rings

Valves, guides, and seals

Gaskets

Pistons

Heads

Over two months were spent troubleshooting the problem. The root cause

was a dipstick that was too short. The dipstick was installed during the

prototype build. This caused the operator to overfill the crankcase,

resulting in the oil being whipped up by the crankshaft. The correct

dipstick cured the problem.

Again, technicians who can think in non-traditional ways will arrive at the

root cause of the problem.

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4

MASTERMIND

AVAILABLE COLORS:

CLASS EXERCISE 2

A game called "Mastermind" is an exercise that helps test logical, process

oriented thinking, which can solve problems in a more efficient manner.

In the game of Mastermind, one player, "codemaker," makes up a secret

code consisting of a random sequence of four marbles. The other player,

"codebreaker," attempts to guess the code using as few guesses as

possible.

After each guess the codebreaker receives feedback. Feedback consists of

two parts, a number of black pegs indicating how many marbles

codebreaker got exactly right (correct color in the correct position) and a

number of white pegs, indicating how many marbles codebreaker got

almost right (correct color but wrong position). There is no positional

information in the black and white pegs, they merely count how many

marbles were guessed exactly right or almost right.


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Playing the Mastermind game, relates to the diagnosis process because it's

a process of elimination. It helps determine what doesn't work by

eliminating the wrong marbles. Eventually the right combination is

discovered.

A diagnostic process determines the root cause of a fault by eliminating

what does work by testing and evaluating. By knowing what does work,

the fault can be isolated much quicker.

INSTRUCTOR NOTE: More information on the Mastermind game

can be found at the following website:

http://www.geocities.com/Athens/Aegean/2522/MasterMind.html

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Poor System Knowledge

Act on Instinct not Logic

Does not Use or Know Resources

Does not Use or Know Tests

Does not Use or Know Test Equipment

Does not See the Big Picture

NOVICE EXPERT

TROUBLESHOOTING TRAITS

Excellent System Knowledge

Logical Methodical Approach

Uses all Resources Available

Knows What Tests to Perform

Knows How to Use Test Equipment

Sees the Big Picture

TROUBLESHOOTING TRAITS

There are some basic skills or traits that are required to be an effective

troubleshooter. This chart compares the traits that are typical of novice

and expert troubleshooters. While most technician's skills fall somewhere

between the novice and expert, this chart shows what skills are necessary

for efficient diagnosis.

An expert troubleshooter in an unfamiliar situation will quickly assess the

problem and overcome the learning curve. The expert may not have

excellent system knowledge (new system) but has the ability to apply a

logical process and determine the root cause of a problem.

This presentation focuses on the logical process so the technician sees the

"big picture" and avoids going down the wrong diagnostic path. System

knowledge and use of resources are important skills in the troubleshooting

process, but can be taught in system specific classes or learned at the

jobsite while performing diagnosis.


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SEVEN LINKS OF A CHAIN

CLASS EXERCISE 3

Class Exercise 3 emphasizes non-traditional thought as it might be applied

to the problem solving process.

Bill wants to pay Jeff with one link of chain for each of the seven days

that Jeff will be working. The two men do not trust each other. Jeff wants

to be paid in full at the end of each working day. Bill wants to give Jeff

only the number of links he has earned at the end of each day.Unfortunately the chain cutters are in poor condition and only have

enough life left in them to separate one link of the chain. Can only one

link be separated and still satisfy both Bill and Jeff?


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DAY 1DAY 2 DAY 4

SEVEN LINKS OF A CHAINSOLUTION

Day 1 = Day 1Day 2 = Day 2 (Return Day 1)Day 3 = Day 2 + Day 1Day 4 = Day 4 (Return Day 2 + Day 1)Day 5 = Day 4 + Day 1Day 6 = Day 4 + Day 2 (Return Day 1)Day 7 = Day 4 + Day 2 + Day 1

If the third link is cut, Bill can pay Jeff the exact amount of links he has

earned for each day.

This exercise provides an example of a non-traditional give and take

thought process.


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TROUBLESHOOTING STRATEGIES Shotgun Approach - "Parts Replacer"

Thorough Search Approach - "Test Everything"

System Approach - "Get the Schematic"

Split Half Approach - "Divide the System in Two"

Knowledge Based Search - "Picture the System"

TROUBLESHOOTING STRATEGIES

Most troubleshooting processes generally fall into one of several different

types of strategies. Knowing how to apply the strategies or which strategy

to use is not important. The significance of reviewing these strategies is

to recognize that technicians often resort to a strategy (whether right or

wrong) when diagnosing a fault.

The Shotgun Approach, or the trial and error approach results in parts

replacement and tests that are performed randomly and in no particular

order. Success is generally luck. Novices often believe this is the most

time saving and least cost approach. Example: The serviceman receives

an operator complaint that the blade on a track-type tractor will not lift

when the lever is pulled. He operates the machine to confirm the report

and decides there must be no hydraulic oil flow. The serviceman replaces

the pump. He operates the machine and finds the blade still will not lift.


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Using a pressure gauge he finds that the problem is low pressure, not low

flow. He now replaces the much less expensive relief valve which solves

the problem.

INSTRUCTOR NOTE: At this point, insert examples from your own

dealership/experience of the shotgun approach to problem solving.

In the Thorough Search Approach all individual components are tested in

no particular order. The problem may be found, but the process may be

very time consuming and can get bogged down quickly with complex

systems. Example: The serviceman receives an operator complaint that

the late model track-type tractor will not move in either direction. Having

just completed an electronics class, he hooks up Electronic Technician

(ET) and proceeds to find no active or logged faults. He now hooks up

Dataview only to find the main relief valve pressure low. A logical

approach would have been to use the Caterpillar Monitoring System on

the machine and a couple of pressure gauges to determine the problem.


dealership/experience of the thorough search approach to problem

solving.

The System Approach uses systems diagrams or schematics to provide the

technician with a roadmap of the system. The troubleshooter is now

starting to understand not only the WHAT but also the WHY. Many

people function at this level. At times the serviceman stops at the firstpart in the system that he sees that could possibly cause the problem

described. He tends not to pursue all possible causes to determine the true

root cause of the problem.


dealership/experience of the system search approach to problem

solving.

In the Split Half Approach, the area containing the problem is divided in

half and tested to determine in which half the problem lies. This process

of elimination narrows the search, but machine systems dont always

allow for easy testing at a halfway point. The technician must often

devise nonstandard tests to implement the Split Half Approach. This is a

powerful tool in the troubleshooters toolbox. Example: A serviceman

receives an operator complaint that a hydrostatic track-type loader slows

to a crawl or sometimes stops when attempting a turn. He connects a

hydraulic test group to the hydrostatic transmission and finds all pressures

within the normal range. He continues to try to adjust the transmission to

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achieve proper turning by raising adjustments to the upper limits. After a

factory call, he installs an engine tachometer and finds that the high idle

engine speed drops over 150 rpm more than the test specification when

stalling against the implement hydraulic pump. This test, if done initially,

would have immediately split the problem between the hydrostatictransmission and the engine, indicating the problem was low engine

power.


dealership/experience of the split-half approach to problem solving.

When using the Knowledge Based Search, the technician conceptualizes

system faults to help devise meaningful and productive tests to verify

theories. The technician asks questions to narrow the focus to the most

likely causes of the problem, which speeds the troubleshooting process

and improves efficiency. It allows the troubleshooter to conceptualize

system faults in their minds so they can devise meaningful and productive

tests to verify their theories. The Knowledge Based Search strategy

incorporates parts of all the strategies.


dealership/experience of the knowledge based search approach to

problem solving.

NOTE: Follow a logical process and do not get locked into one

particular strategy.

INSTRUCTOR NOTE: Have the students discuss situations where

they may have used the troubleshooting strategies.

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9

CLASS EXERCISE 4

This is another exercise designed to show the change in the thought

process when becoming a better troubleshooter.

Objective: Make four identical triangles using only the six toothpicks

provided.

All triangles must be the same length on each side and equal in area.

Most people will try to arrange the toothpicks while laying them flat on

the table. Is this the only way to approach the problem? Think about

solving this problem in three dimensions.

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SIX TOOTHPICKS


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10

Build a pyramid out of the toothpicks to solve the problem.

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SIX TOOTHPICKSSOLUTION

BUILD A PYRAMID


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Receive, InterpretReport

DoesProblem

TrulyExist?

OperatorInduced?

Look for ObviousCheck Basics

Gather DiagnosticAids and Info

Clear ProblemInstruct Operator

Apply SelectedProcess

Identify Root Cause,Generate Solution

Solved?

Repair and Follow upComplete paperwork

Done

N

Y

Y

N

N

Y

TROUBLESHOOTING PROCESS FLOWCHART

TROUBLESHOOTING PROCESS

This flowchart outlines a basic troubleshooting process. Its important to

realize that this process chart does not necessarily have to be followed in

the exact order shown here. The goal is to use the steps of the process

based on the nature of the fault.

The problem may be so obvious that a technician can identify both the

problem and the cause immediately. Depending on technician experienceand the scope of the problem, the technician may mentally process these

flowchart steps in an instant.

However, there are other problems that are not so obvious which may take

a technician several hours of hard mental and physical labor to come to a

conclusion and repair the problem successfully. The problem or failure

may be obvious, but an organized investigation may be required to

identify the cause.


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Receive, Interpret

Report

DoesProblem

TrulyExist?

OperatorInduced?





Identify Root CauseGenerate Solution

Solved?


Done

N

Y

Y

N

N

Y


VERIFY

IDENTIFY INTERVIEW

OPERATE

DEFINE

The first step in the troubleshooting process is to verify that a problem

truly exists. Identify the problems and the symptoms and to talk to the

operator who actually operates the equipment.

Gather information and write a problem statement that accurately

describes the problem and allows the writing of is/is not statements. The

expert troubleshooter makes sure to spend as much time as required in this

phase of the process. Time spent "up front" can have a huge effect on the

overall time required to solve the problem.

This initial information can be received from a service manager or by a

phone conversation with the owner, job site manager, engineer, operator,

or by other means. This information is not always as complete and

detailed as the technician needs to diagnose a problem. However, with a

Serial Number and Arrangement Number, and the initial information, the

technician will be able to acquire the history folder, service manuals,

bulletins, proper tools, and parts.


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Ask what the problem is, when the condition occurs, where or under what

conditions the problem occurs, how often the problem occurs, and if the

problem is intermittent.

Verify the problem exists. Operate the machine to duplicate the problem,

preferably under similar operating conditions. Compare the operation to a

known good machine. Perform sensory checks such as looking, listening,

touching, and smelling to verify a problem exists.

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DoesProblem

TrulyExist?

OperatorInduced?





Solved?


Done

N

Y

Y

N

N

Y


SIMPLE

QUICK

CHEAP


When troubleshooting, always perform a visual inspection first to look for

the obvious. Its important to remember to check the basics. The Pareto

principal states that "20% of the sources cause 80% of the problems."

Many problems appearing complex are really just a manifestation of a

simple problem.

When devising tests to check the basics, the simple, quick, and cheap

philosophy should guide our decisions. Typical items that should be

inspected during a visual inspection include checking fluid levels,checking lines and connections for damage or leaks, and checking control

linkages for damaged or broken components.

Don't spend too much time checking the basics because the purpose is to

eliminate the obvious causes of the problem and not perform extensive

testing. The visual inspection will also help identify what other resources

may be required to further investigate the problem.


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DoesProblem

TrulyExist?

OperatorInduced?




Solved?

Repair and Follow up

Complete paperwork

Done

N

Y

Y

N

N

Y


DIAGNOSTIC TOOLS

SERVICE INFORMATION

PEERS OR SPECIALISTS



Based on the machine information gathered and the visual inspection,

additional resources may be required to further investigate the problem.

There are several resources available to help gain system knowledge and

pinpoint machine problems.

Finding information within the Caterpillar network is essential when it

comes to improving troubleshooting procedures. The traditional sources

of this information includes service information found in the Service

Information System (SIS). Nontraditional sources of information withinthe Caterpillar network would include items such as the knowledge

network or a web based resource comprised of technicians and employees

world wide.


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INSTRUCTOR NOTE: Have the students brainstorm a list of

Caterpillar resources while you write them on the board. Don't

discourage any suggestions by the students. Discuss the resources

listed and answer any questions. Below is a partial list of resources to

begin the discussion:

Diagnostic tools

Data View

Caterpillar Electronic Technician

Systems Operation, Testing, and Adjusting Manuals

Troubleshooting Manuals

Schematics

Special Instructions

Service Letters

Product BulletinsTechnical Marketing Information (TMI)

Disassembly and Assembly Manuals

Caterpillar Product Analysts

Caterpillar Service Training

Other Technicians/Co-workers

Operation and Maintenance Manuals

Diagnostic Advisor

Caterpillar Knowledge Network

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DoesProblem

TrulyExist?

OperatorInduced?





Solved?


Done

N

Y

Y

N

N

Y


LIST POSSIBLE FAULTS

DEVISE TESTS

PERFORM TESTS

COLLECT DATA


If the basic checks have failed to solve the problem, begin listing possible

faults so a more detailed investigation may be pursued. A list of possible

faults can be found in the troubleshooting section of the machine service

information. Identify all systems and components that could be causing

the problem, including the least obvious.

The information should be placed on a sheet of paper in a chronological

order according to the manner in which the technician would want to

check or test the machine. The chronological order should be "easiest andcheapest to check first."

In some cases the technician may need to return to different sources to

gather information to help strengthen the thought process. This

information needs to be more detailed and precise.


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Create a list of tests that should be performed based on the possible faults

identified. Describe what the tests would determine and what results are

expected from the testing. Prioritize the tests as to which sequence they

should be performed in. As a general rule, always do the easiest tests

first. Also, list diagnostic tooling required to perform the tests.

In some cases there may be more than one problem affecting the way the

machine is operating. Separate the different symptoms. If possible, work

each symptom separately.

Use the completed checklist to plan appropriate action and connect the

tooling. Testing is a time consuming and expensive operation. Collect all

data needed to ensure that all requirements are fulfilled with one test (if

possible). Connect all test equipment with a systematic approach to

reduce the number of possible causes and eliminate any preconceived

ideas. If some risk is involved, the machine is not operable, or the testing

did not reveal the needed information, obtain data from other sources, as

necessary.

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DoesProblem

TrulyExist?

OperatorInduced?





Solved?


Done

N

Y

Y

N

N

Y


ANALYZE TEST DATA

IDENTIFY CAUSE


When the test data has been collected, compare the test data with some

baseline data. When analyzing data, be very careful of preconceived

ideas. Analyzing data includes evaluating component performance,

understanding how components and systems interact, how components

work correctly, and how the system reacts if a component is faulty.

Never correct the failure without identifying the cause. An analysis of the

data should identify the problem. If the cause is not yet obvious, more

testing, data collection, and analysis will be necessary. The technician

may have to vary one thing at a time to test the possible cause, especially

when not familiar with the system.

INSTRUCTOR NOTE: Explain to the students that during

troubleshooting, the majority of the time is spent performing tests

and interpreting the test results.


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DoesProblem

TrulyExist?

OperatorInduced?





Solved?


Done

N

Y

Y

N

N

Y


COMPLETE REPAIR

VERIFY REPAIR

DOCUMENT REPAIR


After isolating the component(s), which is suspected to be causing the

problem, either adjust, repair, or replace the component(s).

When repairing a machine, never assume the new part is OK. Install the

new or rebuilt part and return the machine systems to original

configuration. A well defined outline should have been completed so that

no steps are left out of the service report. There are six basic repair

procedures that should be followed closely:

1. Always wear safety clothing and practice safety precautions andrules;

2. Protect all new and used parts from damage;

3. Clean and lubricate the machine parts as per the Service Manual;

Do not place alternative lubricants on parts;

4. Use the proper tools;

5. Follow the correct procedure using the appropriate Caterpillar

literature; and

6. Pay close attention to details.


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After completing the repair, always verify the machine is operating

correctly. Perform an operational check or a specific test that ensures the

repair has fixed the problem. If the fault remains after checking the repair

(or a new fault appears) go through the troubleshooting procedure again.

Is there is a basic process that can be changed to prevent or minimize the

problem from reoccurring? For example, do the operating conditions

require more frequent filter changes than normal?

After the repair is completed and verified, complete the required

documentation (service report). Document the problem, the cause, and

what was required to repair it. Build a database for future use. Accurate

and complete information on the service report is important because it

stays with the machine and is useful when diagnosing future problems.

Troubleshooting information can take many forms, such as a well-planneddata sheet that is filled out on a regular basis, or a simple log sheet if it

has frequent entries. It can be a dealer service report, notes written on a

log book margin, casual observations from an operator, or a chief

engineer that has a good memory. When the need exists to solve a

machine problem, or piece together a number of clues that will identify

the cause of a failure, all information is significant. Service personnel

should encourage their customers to keep good machine records.

NOTE: When troubleshooting a machine, the troubleshooting steps

may overlap and be repeated many times unconsciously during theprocess. On the other hand, for difficult problems the steps may have

to be deliberately outlined and the data collected, organized, and

carefully analyzed to solve the problem.

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CASE STUDY

The case study provided (Serviceman's Handout No. 1) is an actual fault

that was diagnosed and repaired in the field.

INSTRUCTOR NOTE: Distribute the case study and have the

students list the diagnostic steps that were performed during the fault

diagnosis on the Case Study Worksheet.

Ask the students if the bail fault could have been diagnosed more

efficiently. Discuss the completed worksheets. Create a new list of

diagnostic steps with the students, utilizing the troubleshooting

process. List reference material and tooling that could have been

used.

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CASE STUDY

Bail Not Operating

627G Wheel Tractor-Scraper


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19

CONCLUSION

The real world is never as simple as the diagrams depicted in training

courses appear. Thats why the basics must be emphasized. Failure to

follow a process can often lead to disastrous results. Eliminate the

obvious. Follow the troubleshooting process. Use the highest level

troubleshooting approach that you are comfortable with. Follow up after

the troubleshooting process and dont try to shortcut it. Work smarter, not

harder.

INSTRUCTOR NOTE: At this time, the students should

demonstrate the use of the troubleshooting process by diagnosing

instructor installed machine faults. Have the students complete a

Troubleshooting Worksheet for each machine fault diagnosed.

After the students have completed diagnosis, review the diagnostic

steps performed and complete the Troubleshooting Review

Worksheets with the students to evaluate their understanding of the

troubleshooting process.

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1. Technician using diagnostic tool

2. Washer and bolt exercise

3. Washer and bolt exercise answer

4. Mastermind exercise

5. Troubleshooting traits

6. Seven links of a chain exercise

7. Seven links of a chain exercise answer

8. Troubleshooting Strategies

9. Six toothpicks exercise

10. Six toothpicks exercise answer

11. Troubleshooting process flowchart

12. Troubleshooting process flowchart (receive

and interpret report)

13. Troubleshooting process flowchart (look for

obvious and check basics)

14. Troubleshooting process flowchart (gather

diagnostic aids and info)

15. Troubleshooting process flowchart (apply

selected process)

16. Troubleshooting process flowchart (generate

solution)

17. Troubleshooting process flowchart (repair

and follow up)

18. Case study

19. Technician using diagnostic tool

VISUALS LIST

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SERV3151 - 32 - Serviceman's Handout No. 1

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627G Wheel Tractor-Scraper Case Study

Bail Does Not Operate

The service department was informed that the bail would not operate. The technician operated the

machine to verify that the problem existed. The bail would not raise, although it did appear to jerk very

slightly when the bail switch was activated. When operating the machine, the technician also noticed

that the cushion-hitch did not function. The ejector, bowl, and apron functions appeared to operate

normally.

The technician noticed that there were no active codes on the Caterpillar Monitoring System. Next, the

technician used ET to look at logged codes and to check other parameters. There were no codes related

to the bail problem. By studying the hydraulic schematic, the technician was able to determine that the

pump, which provided oil flow to the bail, also provided oil flow to the cushion-hitch and implement

pilot system.

Main system pressure was checked. The pressure was 1930 kPa (280 psi) and should have been

15160 kPa (2200 psi). When the technician reviewed the print, he noticed that both the cushion-hitch

valve and the bail control valve had possible paths for system leakage to the tank. The decision was

made to isolate one of the systems to pin point the problem. The cushion-hitch supply was blocked off,

but the bail still would not raise. The supply line to the cushion-hitch was reattached. Next, the bail

supply oil was blocked off and the cushion-hitch operated normally. The technician assumed the

problem was in the bail control valve.

The drawing of the bail control valve in the systems operation manual was used to determine whatcomponent of the valve might allow supply oil to flow to the tank. The technician decided to start with

the line relief valve. Upon disassembly, the technician discovered that a small snap ring had fallen off

the line relief spool allowing the spool to exit the end of the relief valve body. This provided a path for

supply oil to travel directly to the tank. System pressure was not able to build to the required 15160 kPa

(2200 psi).

All hydraulic lines were connected and fluid levels were checked. All hydraulic systems functioned

correctly. As a last step, the technician checked all oil pressures to ensure that all systems were adjusted

according to specification.


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ReceiveProblem

Report

InterpretProblem

Report

LocateEquipment

GatherHistory,check

Configuration

InterviewO

perator

VerifySymptoms

OperateEquipment

DoesProblem

TrulyExist?

RefineProbStatement

ifRequired

Operator

Induced?

ClearProblem

Ins

tructOperator

Lookfortheobvious

CheckBasics(within

reason)

Problem

Solved?

PM

Needed?

DoPreventative

Maintenance

GatherDiagnostic

Aids

Mak

eFinalChecks

V

erifyRepair

YY

Y

N

N

N

N

ApplySelecte

d

DiagnosticProc

ess

Complete

Paperwork

Thorough

Search

System

Search

Split/

Half

Knowledge

Based

Generate

Solution

Problem

Solved?

Implement

Repair

FollowUp?

Shotgun

Approach

TROUBLES

HOOTINGFLOWCHART

N

Y

Y


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Case Study Worksheet

Directions: Use this worksheet to list each step performed during the case study. List the tooling and

reference material that is stated in the case study.

1. __________________________________________________________________________

Reference Material: _________________________________________________________

Tooling: __________________________________________________________________

2. __________________________________________________________________________


Tooling: __________________________________________________________________

3. __________________________________________________________________________


Tooling: __________________________________________________________________

4. __________________________________________________________________________


Tooling: __________________________________________________________________

5. __________________________________________________________________________


Tooling: __________________________________________________________________

6. __________________________________________________________________________


Tooling: __________________________________________________________________

7. __________________________________________________________________________


Tooling: __________________________________________________________________


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10/02

Troubleshooting Worksheet

Directions: Use this worksheet to list each step performed while diagnosing a machine fault. Below

each step list any reference material and tooling used.

Operator Complaint:_________________________________________________________

1. __________________________________________________________________________


Tooling: __________________________________________________________________

2. __________________________________________________________________________


Tooling: __________________________________________________________________

3. __________________________________________________________________________


Tooling: __________________________________________________________________

4. __________________________________________________________________________


Tooling: __________________________________________________________________

5. __________________________________________________________________________


Tooling: __________________________________________________________________

6. __________________________________________________________________________


Tooling: __________________________________________________________________

7. __________________________________________________________________________


Tooling: __________________________________________________________________


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Troubleshooting Worksheet (Continued)

8. __________________________________________________________________________


Tooling: __________________________________________________________________

9. __________________________________________________________________________


Tooling: __________________________________________________________________

10. __________________________________________________________________________


Tooling: __________________________________________________________________

11. __________________________________________________________________________


Tooling: __________________________________________________________________

12. __________________________________________________________________________


Tooling: __________________________________________________________________

13. __________________________________________________________________________


Tooling: __________________________________________________________________

14. __________________________________________________________________________


Tooling: __________________________________________________________________

15. __________________________________________________________________________


Tooling: __________________________________________________________________


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10/02

Troubleshooting Review Worksheet

Directions: The instructor and students should complete this worksheet together after the machine fault

has been repaired. Could the diagnosis have been performed more effectively? If so, list the diagnostic

steps, reference materials, and tooling that might have pinpointed the fault quicker.

Operator Complaint:_________________________________________________________

1. __________________________________________________________________________


Tooling: __________________________________________________________________

2. __________________________________________________________________________


Tooling: __________________________________________________________________

3. __________________________________________________________________________


Tooling: __________________________________________________________________

4. __________________________________________________________________________


Tooling: __________________________________________________________________

5. __________________________________________________________________________


Tooling: __________________________________________________________________

6. __________________________________________________________________________


Tooling: __________________________________________________________________

7. __________________________________________________________________________


Tooling: __________________________________________________________________


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Troubleshooting Review Worksheet (continued)

8. __________________________________________________________________________


Tooling: __________________________________________________________________

9. __________________________________________________________________________


Tooling: __________________________________________________________________

10. __________________________________________________________________________


Tooling: __________________________________________________________________

11 __________________________________________________________________________


Tooling: __________________________________________________________________

12 __________________________________________________________________________


Tooling: __________________________________________________________________

13 __________________________________________________________________________


Tooling: __________________________________________________________________

14. __________________________________________________________________________


Tooling: __________________________________________________________________

15. __________________________________________________________________________


Tooling: __________________________________________________________________


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INSTRUCTOR NOTES

SERV3151 - 39 -

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Diagnostico y Troubleshooting

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Transcript of Diagnostico y Troubleshooting