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Republic of the Philippines
Department of Education
PUBLIC TECHNICALVOCATIONAL
HIGH SCHOOLS
PUBLIC TECHNICALVOCATIONAL
HIGH SCHOOLS
Unit of Competency: Test and Repair Electrical Wiring/Lighting
System
Module No.: 2
Module Title: Testing and Repairing
Wiring/Electrical System
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TABLE OF CONTENTS
Page
How to Use this Module ………………………………………………...
Introduction………………………………………………………………..
Technical Terms…………………………………………………………...
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Learning Outcome 1 ………………………………………………………
Learning Experiences/ Activities ………………………………..
Information Sheet 1 …………………………………………….
Self Check 1 …..………………………………………………..
Operation Sheet 1... …………………………………………….
Learning Outcome 2….……………………………………………………
Learning Activity ………………………………………………..
Information Sheet 1 ……………………………………………..
Self Check 1 ……..……………………………………………..
Operation Sheet 1... ………………………………….………….
Assessment Performance ………………………………………..
Learning Outcome 3……………………………………………………….
Learning Activity………………………………………………..
Information Sheet 1………………………………………………
Self Check 1……………………………………………………...
Self Check 2……………………………………………………...
Self Check 3……………………………………………………...
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HOW TO USE THIS MODULE
Welcome to the Module “Testing and Repairing Wiring/Electrical
System”. This module contains training materials and activities for you to
complete.
The unit of competency “Test and Repair Electrical Wiring/Lighting
System” contains the knowledge, skills and attitudes required for
Automotive Servicing course required to obtain the National Certificate
(NC) level I & II.
You are required to go through a series of learning activities in order to
complete each of the learning outcomes of the module. In each learning
outcome there are Information Sheets,, Operation Sheets and Activity
Sheets. Do these activities on your own and answer the Self-Check at the
end of each learning activity.
If you have questions, don’t hesitate to ask your teacher for assistance.
Recognition of Prior Learning (RPL)
You have already some basic knowledge and skills covered in this module
because you have been working for some time; and already completed
training in this area.
If you can demonstrate competence to your teacher in a particular skill,
talk to your teacher so you don’t have to undergo the same training again. If
you have a qualification or Certificate of Competency from previous trainings
show it to him/her. If the skills you acquired are consistent with and
relevant to this module, they become part of the evidence. You can present
these for RPL. If you are not sure about your competence skills, discuss this
with your teacher.
After completing this module, ask your teacher to assess your
competence. Result of your assessment will be recorded in your competency
profile. All the learning activities are designed for you to complete at your
own pace.
In this module, you will find the activities for you to complete and
relevant information sheets for each learning outcome. Each learning
outcome may have more than one learning activity.
This module is prepared to help you achieve the required competency, in
receiving and relaying information. This will be the source of information
that will enable you to acquire the knowledge and skills in Testing and
Repairing Wiring/Lighting System independently at your own pace with
minimum supervision from your teacher.
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Program/Course:
AUTOMOTIVE SERVICING NC 1
Unit of Competency:
Test and Repair Wiring/Lighting System
Module Title:
Testing and Repairing Wiring/Lighting System
INTRODUCTION:
This module contains information and suggested learning activities on
testing and repairing electrical system.
It includes instructions and
procedure on how to use hand tools and electrical instruments in
accordance to manual instructions and specification.
Completion of this module will help you understand the succeeding
module on Test and Repair Wiring/Lighting System.
This module consists of three (3) learning outcomes. Each learning
outcome contains learning activities with instruction sheets. Before you
follow the instruction, read the information sheets and answer the selfcheck and activities provided to assess your competence by your teacher.
He/she will check if you have acquired the knowledge necessary to perform
the skill portion of the particular learning outcome.
Upon completing this module, report to your teacher for assessment. If
you pass the assessment, you will be given a certificate of completion.
SUMMARY OF LEARNING OUTCOMES
Upon completion of the module, you should be able to:
LO1. test electrical system for open and short circuits to determine faults;
LO2. repair electrical system; and
LO3. test and repair starting system.
ASSESSMENT CRITERIA
Refer to assessment criteria of learning outcomes 1-3 of this module.
PREREQUISITES
The learner should be able to read electrical diagram
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TECHNICAL TERMS
AMMETER a test meter to measure current draw
BACK UP LIGHTS a light that illuminates the back of the car when the
transmission is shifted in reverse.
CONTINUITY refers to the circuit being continuous with no open.
DIMMER SWITCH a two position switch operated by the driver to select
High or low head light beam.
FUSE a replaceable circuit protection device that will melt. Should the
current passing through it exceeds its rating.
GROWLER test equipment used to test starter armatures for shorts and
grounds. It produces a very strong magnetic field that is capable of inducing
a current flow and magnetism in a conductor.
OHMMETER a test meter resistance and continuity in a circuit.
OPEN CIRCUIT a term used to indicate that current flow is stopped. By
opening the circuit, the path for electron flow is broken.
PARKING LIGHTS a light that marks the front of a parked vehicle and to
mark the front of a vehicle if a headlamp fails.
RESISTANCE opposition to current flow.
SHORT CIRCUIT an unwanted electrical path; sometimes this path goes
directly to ground.
SOLENOID CIRCUIT RESISTANCE TEST diagnostic test used to determine
the electrical condition of the solenoid and the control circuit of the starting
system.
STATOR the stationary coil of the ac generator in which current is
produced.
TURN SIGNAL LIGHTS a lights when indicates an intended change in
directions by flashing lights on the side towards which the turn will be made.
TROUBLESHOOTING the diagnostic procedure of locating and identifying
the cause of the fault. It is a step-by-step process of elimination by use of
cause-and-effect.
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Program/Course:
Automotive Servicing
Unit of Competency:
Test and Repair Wiring/Lighting System
Module Title:
Testing and Repairing Wiring/Lighting System
Learning Outcome 1: Test electrical system of open and short circuit to
determine faults.
Assessment Criteria

Correct information is assessed and interpreted from appropriate
manufacturer’s specifications.

Tests are to determine faults using appropriate tools and techniques.

Faults are administered, interpreted and applied

Tests are completed without causing damage to the workplace property or
vehicle.
Resources

Basic Automotive Electricity
By: Felizardo Francisco & Orvil Molina

Automotive Electricity, Electronics and Computer Controls
By: Barry Hollembeak
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LEARNING EXPERIENCES/ACTIVITIES
Learning Outcome 1: Test Electrical System
Learning Activities
1. Read the attached information
sheet no. 1. Purpose of wiring
lighting circuit and components.
2. Answer self-check no.1 to test your
knowledge on the purpose or
importance of wiring lighting
circuit and components.
Special Instructions
 Try to answer self-check without
looking at the information sheet.
 Try to answer the self-check with in
the least possible time allotment.
3. Compare your answer to answer
key LO 1.
 Try to answer assessment criteria
4. After completion, read the
operation sheet no. 1.
5. Perform test wiring/lighting circuit
on wiring mock-up.
base on operation sheet no.1.
 Return Demo
INFORMATION SHEET No. 1
Automotive Lighting System and Components
The automobile uses electric lighting to provide the illumination
or light needed to safely operate the vehicle especially night time, the various
lights provide vision and information to the driver to other drivers and
pedestrians. The automotive lighting system consists of the components. A
wire, switches, relays that operate the interior and exterior lights on car.
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Fig. 15 Schematic wiring diagram of automotive lighting system
Exterior Lights
Typically include the headlights, signal lights, stoplights,
parking lights, back up lights and side marker lights.
Interior Lights
Normally include the dome light, instrument light, in the dash
board, trunk light.
Fig. 16 Components of lighting system
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Head Lamp Circuit
The headlight circuit is composed of the headlights, dimmer
switch, fuse, light switch, and storage battery. Although the ammeter
properly belong to the charging system, it may also be considered as part of
the lighting system if the current used in this system passes through the
ammeter. Note that the headlights have two filaments, one for the bright and
the other for dim lights. Both these filaments are connected to a common
ground terminal. However, only one of these filaments lights at a time.
Switching the headlights from bright to dim or from dim to
bright is accomplished by means of the dimmer switch. The fuse, which may
be found in a fuse box, protects the headlights from damage or burning out
due to grounded live wire. The fuse burns out to cut off the flow of excessive
current.
The light switch is the main switch of the lighting system. It
controls the flow of current to the headlight circuit, taillights, and
instrument panel lights
Fig. 16 Schematic diagram of headlight circuit
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Head Lamp Switch- is an on/off switch and rheostat in the dash
panel or on the steering column.
Fig. 17 Exploded view of headlight switch
Dimmer Switch- controls the high and low head lamp beam function.
This switch may be mounted on the steering column or flow board.
HIGH__________
LOW___________
BATTTERY________
Dimmer Switch
Fig. 18 dimmer switch
Directional Light Circuit
The turn light system basically consists of a fuse, switch, flasher, unit,
turn light bulbs, indicator bulbs and related wiring. The turn signal light
are used by the driver of an automotive vehicle to indicate his intention of
driving either to the right or to the left. A directional signal light switch is
used by the driver to operate the right signal lights if his intention is to drive
to the drive to the right, or the left signal lights if his intention is to drive to
the left side.
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Fig. 19 Turn signal light lever
Fig. 20 Schematic diagram of turn signal light circuit
Emergency Light System
The emergency light system also named hazard warning system,
the emergency light switch is normally mounted on the steering
column, it is usually a push-pull switch.
Stop Light Circuit
The stop light system is commonly made up of a fuse, brake
light switch, two rear lamps, and wiring. The brake light switch is
normally mounted on the brake pedal.
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Fig. 21 (a) off position (b) on position of stoplight switch
Fig. 22 A typical schematic diagram of stoplights circuit
Back-up Light Circuit
A back-up is typically has a fuse, transmission mounted switch,
two back-up lamp and wiring to connect these component.
The back lamp switch closes the light circuit when the
transmission is shifted into reverse, to illuminate the area behind the
car.
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Fig. 23 A simple diagram of back-up light circuit
INFORMATION SHEET No. 2
Lighting Circuit Repair and Diagnosis
The lighting system of the vehicle is becoming very complex.
There may be over 50 light bulbs and hundreds of feet of wiring in the
lighting circuits. The circuits include circuit protectors, switches, lamps,
and connectors. Any failure requires a systematic approach to diagnose,
locate, and correct the fault in the minimum amount of time.
The importance of lighting system cannot be overemphasized.
The lighting system should be checked whenever the vehicle is brought into
the shop for repairs. Often a customer may not be aware of a light failure. If
a lighting circuit is not operating properly there is a potential danger to the
driver and other people. When today’s technician performs repairs on the
lighting systems, the repairs must assure vehicle safety and meet all
applicable laws. Be sure to use the correct lamp type and size for the
application.
Before performing any lighting system tests:
a. Check first the battery for state of charge.
b. Also be sure all cable connections are clean and tight.
c. Visually check the wires for damaged insulation, loose
connections, and improper routing.
When troubleshooting the lighting system, if only one bulb is
not operating it is usually faster to replace it with a known good unit
first. Check the connector for signs of corrosion. When testing the
circuit with a voltmeter, or test light, check those components that
can be easily accessed first.
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SELF CHECK No. 1
LO 1. TEST ELECTRICAL SYSTEM
Direction:
On your answer sheet, write the letter of your answer
_______ 1. The exterior lights consists of several components except
one
a. signal light
c. parking light
b. stop light
d. dome light
_______ 2. The type of switch that control the high and low head
lamp beam function
a. signal switch
c. dimmer switch
b. hazard switch
d. stop light switch
_______ 3. The components of exterior light which is mounted on the
the brake pedal
a. back-up light
c. emergency light
b. stoplight
d. signal light
_______ 4. The back-p light switch is mounted on the side of the..
a. transmission
c. differential
b. engine
d. brake pedal
_______ 5. Type of lighting system that permit the driver to turn
the vehicle to the left or right.
a. stop light system
c. back-up light system
b. signal light system
d. head lamp system
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OPERATION SHEET No. 1
Connecting Back up Light Circuit
CONDITIONS:
Supplies and Materials

Automotive wires
Tools




Electrical Pliers
Long nose plier
Test light
Screw Driver
Equipment


Battery 12 volts
Electrical mock-up/Vehicle
Plan/Working Drawing
PROCEDURE
1. Prepare the necessary tools and materials/equipment
2. Connect a wire to the lamp specified as the back-up light to the backup switch found on the transmission.
3. Connect the other terminal to one terminal of the fuse box.
4. Connect a wire from the fuse box to the ACC terminal of the ignition
switch
.
5. Connect a wire from the fuse box to the AM terminal of the ignition
switch.
6. Connect a wire from AM terminal to the positive terminal of the
amphere, and a wire from negative terminal to the positive terminal of
the battery.
7. Connect the negative terminal of the battery to the ground a part of
the vehicle.
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Program/Course:
Automotive Servicing
Unit of Competency:
Test and Repair Wiring/Lighting System
Module Title:
Testing and Repairing Wiring/Lighting System
Learning Outcome 2. Repair Electrical Circuit
ASSESSMENT CRITERIA:
1. Correct information is assessed and interpreted using appropriate
tools and equipment
2. Necessary repairs are carried out using appropriate tools, techniques
and materials
3. Electrical circuit is repaired without causing damage to the work
place, property or vehicle
Resources

Basic Automotive Electricity
By: Felizardo Francisco & Orvil Molina

Automotive Electricity, Electronics and Computer Controls
By: Barry Hollembeak
LEARNING EXPERIENCES/ACTIVITIES
Learning Outcome 2: Repair Electrical Circuit
Learning Activities
1. Read the attached information
sheet no.1 Safety Measures in
Repairing Electrical Circuits.
2. Answer self check LO 2-1 to test
your knowledge.
3. Compare your answer to answer
key LO2-1.
4. Read and perform operation sheet
no. 1 on repair/replace of electrical
system
5. Call your teacher for evaluation.
Special Instructions
 Refer to manufacturer’s service
manuals on repairing electrical
circuit.
 Answer the self check without looking
at the information sheet.
 Try to answer the self check with in
the least possible time allotted.
 Refer to operation sheet no.1.
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INFORMATION SHEET No. 1
SAFETY MEASURE’S IN REPAIRING ELECTRICAL CIRCUIT
Safety is an inherent responsibility the teacher, he further outlined
that assignment of safety responsibility in all students is a basic
requirement. Most accidents can be prevented if all students cooperate in
eliminating unsafe condition and acts. To this end, each individual is
responsible for understanding and applying safety rules, standards, and
regulations in all activities safety consciousness will help prevent personal
injury and damage to property.
The lighting system of the vehicle should be check whenever the
vehicle is brought into the shop for repairs. Often a costumer may not be
aware of a light failure. If a lighting circuit is not operating properly there is
a potential danger to the driver and other people.
The electrical circuit of the vehicle is becoming very complex, there
maybe over 50 light bulbs and hundreds of feet of wiring in the lighting
circuits. The circuits include protectors, switches, lamps, and connectors.
Any failure requires a systematic approach to diagnose, locate and
repair or correct the fault in the minimum of time. When performing repairs
on the lighting or electrical circuits/systems, the repairs must assure
vehicle safety and meet all the applicable laws, be sure to use the correct
lamp type and size for the application.
Before performing any lighting systems test or repair, check the
battery connections, also be sure all cable connections are remove visually
check the wires for damage and insulation, loose connections and improper
routing.
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SELF-CHECK No. 2
REPAIR ELECTRICAL SYSTEM
DIRECTION: On your answer sheet, write the letter of your answer.
__________1. Before performing any lighting system repairs or tests check
the following except one.
a.) battery
c.) cable connection
b.) tire
d.) wires for damage
_________ 2. All are the circuits include in the vehicle except.
a.) protectors
c.) lamps
b.) switches
d.) battery
______ ___3. The lighting systems of the vehicle should be checked to
avoid.
a.) danger to the driver and other people
b.) improper functioning of the lighting circuits
c.) prevent injury and damaged to property
d.) all of the above.
_________4. In repairing the lighting system of the vehicle the following
must be observed.
a.) be sure to use the correct lamp types
b.) size of the wire to be use
c.) assure safety at all times
d.) all of the above
_________5. How many light bulbs and feet of wiring in the lighting circuits.
a.) 10 bulbs and 2 feet of wire
b.) 15 bulbs and 3 feet of wire
c.) 50 bulbs and hundreds of feet of wiring
d.) 20 bulbs and 5 feet of wires
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OPERATION SHEET No. 1
Connecting Back up Light Circuit
CONDITIONS:
Supplies and Materials

Automotive wires
Tools




Electrical Pliers
Long nose plier
Test light
Screw Driver
Equipment


Battery 12 volts
Electrical mock-up/Vehicle
Plan/Working Drawing
PROCEDURE
1. Prepare the necessary tools and materials/equipment.
2. Connect a wire to the lamp specified as the back-up light to the backup switch found on the transmission.
3. Connect the other terminal to one terminal of the fuse box.
4. Connect a wire from the fuse box to the ACC terminal of the ignition
switch.
5. Connect a wire from the fuse box to the AM terminal of the ignition
switch.
6. Connect a wire from AM terminal to the positive terminal of the
ampere, and a wire from negative terminal to the positive terminal of
the battery.
7. Connect the negative terminal of the battery to the ground a part of vehicle body.
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OPERATION SHEET NO. 2
HEAD LIGHT REPAIR AND REPLACEMENT
CONDITIONS:
Supplies and Materials:
 Headlamp
 Test lamp
 Soldering iron
 Electrical tapes
 Wire terminal
Tools:
 Philip screw drivers
 Standard screw drivers
 Electrical pliers
 Wrenches(Box and Open)
Equipment:
 Battery (12 volts)
 Electrical mock-up/Vehicle
PROCEDURE:
The teacher will discuss the procedure with the students with the aid
of diagram and pictures demonstration. Then the students will do the
procedure themselves.
1. Place fender covers around the work area
2. This type of replacement usually requires the removal of the
bezel.( The bezel is the retaining trim around a component)
Fig. 24 Remove the light bezel.
3. Remove the retaining ring screws and the retaining trim. Do not turn
the two headlight aiming adjustment screw.
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4. Remove the headlight from the shell assembly.
5. Disconnect the wire connector from the back of the lamp.
6. Check the wire connector for corrosion or other foreign materials.
Clean as needed.
Fig. 25 Exploded view of headlight assembly.
7. Coat the connector terminals and the prongs of the new headlight
with the dielectric grease to prevent corrosion.
8. Install the wire connector to the headlight prongs and place the
headlight into the shell assembly. When positioning the headlight, be
sure the embossed number is at the top.
9. Install the retainer trim and fasteners.
10.Check the operation of the headlight.
11.Check headlight aiming as described.
12.Install the headlight bezel.
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PERFORMANCE CRITERIA
LO 2. Repair Electrical Circuit
Workmanship/Performance
POINTS
Quality of Work with application of safety measures
35 – Functional
25 – Not Functional
10 – None Functional
Accuracy of Performance under specified time limit
30 – All procedures are followed
20 – 3-5 procedures are followed
10 – more than 5 procedures are not followed
Proper use of tools/equipment with safety measures
35 – select/use properly of tool/equipment
25 – wrong handling of tools
10 – tools is not suitable for the job.
TOTAL SCORE
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Program/Course:
Automotive Servicing
Unit of Competency:
Test and Repair Wiring/Lighting System
Module Title:
Testing and Repairing Wiring/Lighting System
Learning Outcome 3. Test and Repair Starter Motor
ASSESSMENT CRITERIA:
1. Tests are carried out to determine faults using appropriate tools and techniques.
2. Faults are identified and preferred repair action determined.
3. Starting systems are repaired without causing damage to any workplace property or
vehicle.
4. Information is assessed and interpreted from appropriate manufacturer’s specification.
Resources

Basic Automotive Electricity
By: Felizardo Francisco & Orvil Molina

Automotive Electricity, Electronics and Computer Controls
By: Barry Hollembeak
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LEARNING EXPERIENCES/ACTIVITIES
Learning Outcome 3: Test and Repair Starter Motor
Learning Activities
6. Read the attached information
sheet no.1 Starting system service
caution.
7. Read information sheet no.2
Testing starting system.
8. Answer self check #1 and #2 to
assess your knowledge on testing
starting system.
9. Compare your answer to answer
key #1 and #2.
10.Read and perform operation sheet
no. 1 on disassembling starter
motor.
11.Read and perform operation sheet
no.2 on commutator test.
12.Call your teacher for evaluation.
Special Instructions
 Refer to manufacturer’s service
manuals on repairing electrical
circuit.
 Answer the self check without looking
at the information sheet.
INFORMATION SHEET No.1
TITLE: Starting System Service Cautions
Before beginning any service on the starter system, some
precautions must be observed.
1. Refer to the manufacturer’s manual for correct procedures for
disconnecting a battery. Some vehicles with onboard computers
must be supplied with an auxiliary power source.
2. Disconnect the battery ground cable before disconnecting any of
the starter circuit’s wires or removing the starter motor.
3. Be sure the vehicle is properly positioned on the hoist or on safety
jack stands.
4. Before performing any cranking test, be sure the vehicle is in park
or neutral and the parking brakes are applied.
5. Follow manufacturer’s directions for disabling the ignition system.
6. Be sure the test leads are clear of any moving engine components.
7. Never clean any electrical components in solvent or gasoline. Clean
with low pressure compressed air, denatured alcohol or wipe with
clean rags only.
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Starting System Principles and Components
The internal combustion engine must be rotated before it will
run under its own power. The starting system is a combination of
mechanical and electrical parts that work together to start the engine. The
starting system is designed to convert electrical energy into mechanical
energy. To accomplish this conversion, a starter or cranking motor is used.
The starting system includes the following components: battery, cable and
wires, ignition switch, starter solenoid or relay, starter motor, starter drive
and flywheel ring gear, and starter safety switch.
Fig. 26 Starting system major components.
Major components of the starting system. The solid line represents the
starting circuit. The dashed line indicates the starter control circuit.
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INFORMATION SHEET No. 1
TITLE: TESTING THE STARTING SYSTEM
Insulated circuit resistance test
The insulated circuit resistance test is a voltage drop test that is used to locate high
resistance in the starter circuit. An electrical resistance will have a different pressure or
voltage on each side of the resistance. Voltage is dropped when current flows through
resistance. Most manufacturers design their starting systems to have very little resistance to
the flow of current to the starter motor. Most have less than 0.2 volt dropped on each side of
the circuit. This means the voltage across the starter input terminal to the starter ground
should be within 0.4 volt of battery voltage.
Voltage drops are measured by connecting a voltmeter in parallel with the circuit
section being tested. In order to obtain a voltage drop reading, a load on the circuit must be
applied. The following is the test procedures:
1. Set the volt selector to the 3V position.
2. Connect the test leads depending the type of system being tested.
3. The voltmeter should read off the scale to the right until a load is put on the circuit.
If the meter reads zero, reverse the leads.
4. Disable the ignition system to prevent the vehicle from starting. This may be done
by removing the ignition coil secondary wire from the distributor cap and putting
it to ground.
Fig. 27 Disabling ignition system
5. Crank the engine and observe the voltmeter scale.
This test for voltage drop in the entire circuit, so if voltage drop is excessive the
cause of the drop must be located. To locate cause of the excessive voltage drop,
move the voltmeter lead on the starter toward the battery. With each move of the test
lead, crank the engine while observing the voltmeter reading. Continue to test each
connection until a noticeable decrease in voltage drop is detected. The cause of the
preceding point.
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Ground Circuit Test
A ground circuit test is performed to measure the voltage drop in the ground side of
the circuit. If the starter motor connection to ground is broken or loose, the circuit would be
opened. This could cause an intermediate starter system problem, or a starter motor that will
crank the engine. To perform the ground circuit test, connect the voltmeter leads across the
ground circuit and read voltage drop while cranking the engine. Follow these directions:
1. Set the volt selection to 3V.
2. Connect the positive volt test lead to the starter motor case and the negative test
lead to the ground battery terminal. Make sure any paint removed from the area
where the lead is connected to the case.
3. Crank the engine while observing the voltmeter.
Less than 0.2 volt indicates the ground circuit is good. If more than 0.2 volt is
observed, then there is a poor ground circuit connection. A poor ground circuit connection
could be the result of loose starter mounting bolts, paint on the starter motor case, or a bad
battery ground terminal post connection. Also check the ground cable for high resistance or
for being undersized.
Fig. 28 Connection of voltmeter in circuit ground test.
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OPERATION SHEET No.1
Procedure in Disassembling Starter Motor
1. Always have a clean and organized work area. Prepare tools and materials needed
2. Clean the case and scribe reference marks at each end of the starter and housing
and the frame.
3. Disconnect the field coil connection at the solenoids terminal.
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4. Remove the two screws that attach the solenoid to the starter drive housing.
5. Rotate the solenoid until the locking flange of the solenoid is free, then remove
the solenoid.
6. Remove the through bolts from the end frame.
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7. Remove screw from the cap.
8. Pull out lock and spring
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9. Remove the end frame.
10. Pull out magnetic field
11. Remove the armature from the drive housing. Note: on some units it may be
necessary to remove the shift lever from the drive housing before removing the
armature.
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12. Remove snap ring from the shaft.
13. Pull out retainer.
14. Pull out over running clutch
15. Remove bushing with a hammer and a special service tool (SST)
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Note: In assembling starter motor, perform the reverse procedures in
disassembling.
INFORMATION SHEET No. 2
PARTS OF STARTER MOTOR
Fig. 29 Component parts of starter motor.
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BRONZE BUSHING
FRONT OR NOSE HOUSING
ARMATURE
FIELD COIL ASSEMBLY
PEAR HOUSING
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SHIFT LEVER
MAGNETIC SWITCH
CARBON BRUSH HOLDER
CARBON BRUSH
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THROUGH BOLTS
OPERATION SHEET No.2
Commutator Tests
If a growler is not available, the armature commutator can be tested
for opens and grounds using an ohmmeter. The following procedures should
be followed:
Testing the armature for opens.
1. Set the selector knob of multitester to Rx1.
2. Connect the test leads to any two commutator sectors.
3. Note the reading. There should be zero ohms of resistance.
Note: The armature will have to be replaced if there is resistance.
Fig. 30 Testing the armature for opens.
Testing the armature for shorts to ground.
1. Place the multitester on the Rx2K.
2. Connect one of the test leads to the armature shaft.
3. Connect the other lead to the commutator segments.
4. Check each sector. There should be no continuity to ground.
Note: The armature will have to be replaced if there is continuity.
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Fig. 31 Testing armature for short to ground.
PERFORMANCE CRITERIA
LO 3. Test and Repair Stating System
Workmanship/Performance
POINTS
Quality of Work with application of safety measures
35 – Functional
25 – Not Functional
10 – None Functional
Accuracy of Performance under specified time limit
30 – All procedures are followed
20 – 3-5 procedures are followed
10 – more than 5 procedures are not followed
Proper use of tools/equipment with safety measures
35 – select/use properly of tool/equipment
25 – wrong handling of tools
10 – tools is not suitable for the job.
TOTAL SCORE
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ASSESSMENT PERFORMANCE
LO 3. Test and Repair Starting System
Workmanship/Performance
Points
A. Quality of Work with Application of Safety Measures
35 – Exemplary
25 – Adequate
10 – Need improvement
B. Accuracy of Performance under specified time limit
30 – All work is complete and correct
20 – Minor mistake or error
10 – Some of the work maybe incomplete/misdirected
C. Proper use of tools/equipment with safety measures
35 – Select/use properly of tools/equipment
25 – Wrong handling of tools
10 – Tools is not suitable for the job
TOTAL SCORES
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Self Check No. 1
Answer each of the following answer with the word TRUE if the statement is
correct or FALSE if the statement is wrong. Answer before the number.
1.
The starting system is a combination of mechanical and
2.
electrical parts that work together to start the engine.
An electrical resistance will have a same pressure or
3.
voltage on each side of the resistance.
Voltage drops are measured by connecting a voltmeter
4.
in series with the circuit section being tested.
A ground circuit test is perform to measure the voltage drop
5.
in the ground side of the circuit.
Less than 0.4 volt indicates the ground circuit is good.
Self Check No. 2
Direction: On the blank provided for, write the correct letter of your choice.
1.
No cranking and no lights when the key is turned to start
may be caused all by the following EXCEPT
2.
a. burned out light bulbs
b. an open circuit
c. a dead battery
d. an open fusible link
Voltage is dropped when current flows through __________.
3.
a. Ohms
b. resistance
c. current
d. power
An electrical resistance will have difference pressure or
4.
___________.
a. voltage
b. resistance
c. flow
d. current
A ground circuit test is performed to measure the __________.
a. pressure drop
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b. resistance drop
5.
c. voltage drop
d. heat drop
If the engine cranks slowly but does not start, a possible
cause _________
a. a discharged battery
b. low temperature
c. driver has row down the battery trying to start
d. any of the above
Self Check No. 3
Direction: Select the one correct, best or most probable answer to each
question.
1.
Technician A says the starting system includes a low
current control circuit and a high – current motor circuit.
Technician B says the starting system includes a relay or
solenoid switch and a safety switch. Who is right?
a. A only
b. B only
c. both A and B
2.
d. neither A and B
The overrunning clutch performs all the following except
3.
a. transmits cranking torque to the engine
b. damage the armature if it fails to lock
c. prevents the engine from driving the pinion
d. acts as one – way clutch
The flow of battery connect in the starting motor circuit may
be controlled by means of a _________.
a. mechanical switch
b. electrical switch
4.
c. dimmer switch
d. lock switch
A solenoid is an electromagnetic switching __________.
a.
b.
c.
d.
Device
Gadget
Tools
equipment
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Answer Key
LO1
No. 1
1. d – dome light
2. c – dimmer switch
3. b – stoplight
4. a – transmission
5. b – signal light system
No. 2
1.
2.
3.
4.
5.
B
D
D
D
C
LO3
Self Check No. 1
1.
2.
3.
4.
5.
true
false
false
true
false3
Self Check No. 2
1.
2.
3.
4.
5.
a
b
a
c
d
Self Check No.
1. b
2. d
3. a
4.
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ACKNOWLEDGMENT
Copyright Department of Education 2008
First Published JUNE 2008
This draft was prepared at the Competency-Based Learning Materials
Development Workshop conducted at the Development Academy of the Phils,
Tagaytay City on May 5-10, 2008.
This learning instrument was developed by the following personnel:
Technology Teacher:
George C. Callanta
Don Alejandro Roces, Sr. Science-Technology High School
Quezon City
John M. Diego
Isabela School of Arts and Trades
Isabela
Robert S. Domingo
AFG Bernardino Malolos Trade School
Malolos, Bulacan
Lino A. Olit
Calapan Community Vocational HS
Calapan Mindoro
Romeo DQ. Ibloguin
E. Rodriguez Vocational HS
Sta. Mesa, Manila
Nelson C. Señedo
Tagum National High School
Tagum, Davao del Norte
English:
Belen L. Tado
Tagum National High School
Tagum, Davao del Norte
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Facilitators:
Ms. Beatrice A. Adriano
Encoder:
Rowena S. Fonacier
This work was produced with funding provided by the Department of
Education.
REFERENCES AND FURTHER READING
1. Modern Automotive Service and System
By: James E. Duffy
2. Basic Automotive Service and System
By: Jay Webster
3. Automotive Mechanics, 10th Edition
By: William Crouse and Donald Anglin
4. Manufacturer’s Manual
By: Toyota Corporation
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