relay DODGE NEON 2000 Service Repair Manual

CONTROLLER ANTILOCK BRAKE INPUTS
²wheel speed sensors (four)
²stop lamp switch
²ignition switch
²system relay voltage
²ground
²traction control lamp
²diagnostic communication (PCI)
CONTROLLER ANTILOCK BRAKE OUTPUTS
²amber ABS warning lamp actuation (through
MIC)
²red BRAKE warning lamp actuation (through
MIC)
²traction control lamp actuation (through MIC)
²diagnostic communication. (PCI)
HYDRAULIC CONTROL UNIT (HCU)
The hydraulic control unit (HCU) is mounted to
the CAB as part of the ICU (Fig. 2). The HCU con-
trols the flow of brake fluid to the brakes using a
series of valves and accumulators. A pump/motor is
mounted on the HCU to supply build pressure to the
brakes during an ABS stop.
VALVES AND SOLENOIDS
The valve block contains four inlet valves and four
outlet solenoid valves. The inlet valves are spring-
loaded in the open position and the outlet valves are
spring-loaded in the closed position during normal
braking. The fluid is allowed to flow from the master
cylinder to the wheel brakes.
During an ABS stop, these valves cycle to maintain
the proper slip ratio for each wheel. The inlet valve
closes preventing further pressure increase and the
outlet valve opens to provide a path from the wheel
brake to the HCU accumulators and pump/motor.
This releases (decays) pressure from the wheel brake,
thus releasing the wheel from excessive slippage.
Once the wheel is no longer slipping, the outlet valve
is closed and the inlet valve is opened to reapply
(build) pressure.
There are four other valves in the HCU. These four
remaining valves are used for traction control. Two
traction control (TC) valves, mounted in the HCU
valve block, are normally in the open position and
close only when the traction control is applied. There
are also two shuttle valves which control pressure
return to the master cylinder under ABS and traction
control conditions.
These TC valves are used to isolate the rear (non-
driving) wheels of the vehicle from the hydraulic
pressure that the HCU pump/motor is sending to the
front (driving) wheels when traction control is being
applied. The rear brakes need to be isolated from the
master cylinder when traction control is beingapplied so the rear wheels do not drag. For more
information on the TC and shuttle valves, see TRAC-
TION CONTROL SYSTEM in this section.
BRAKE FLUID ACCUMULATORS
There are two fluid accumulators in the HCU: one
for the primary hydraulic circuit, and one for the sec-
ondary hydraulic circuit. Each hydraulic circuit uses
a 3 cc accumulator.
The fluid accumulators temporarily store brake
fluid that is removed from the wheel brakes during
an ABS cycle. This stored fluid is used by the pump/
motor to provide build pressure for the brake hydrau-
lic system. When the antilock stop is complete, the
accumulators are drained by the pump/motor.
There are two noise dampening chambers in the
HCU on this vehicle equipped with traction control.
PUMP/MOTOR
There are two pump assemblies in the HCU: one
for the primary hydraulic circuit, and one for the sec-
ondary hydraulic circuit. Both pumps are driven by a
common electric motor (Fig. 2). This DC-type motor
is integral to the HCU and is controlled by the CAB.
The pump/motor provides the extra amount of
brake fluid needed during antilock braking. Brake
fluid is released to the accumulators when the outlet
valve is opened during an antilock stop. The pump
mechanism consists of two opposing pistons operated
by an eccentric camshaft. In operation, these pistons
are used to purge fluid from the accumulators back
into the master cylinder circuits. When the antilock
stop is complete, the pump/motor drains the accumu-
lators.
The pump motor is also used to build pressure
when the system goes into traction control mode. For
more information, refer to TRACTION CONTROL
SYSTEM in this section.
The CAB may turn on the pump/motor when an
antilock stop is detected. The pump/motor continues
to run during the antilock stop and is turned off after
the stop is complete. Under some conditions, the
pump/motor runs to drain the accumulators during
the next drive-off.
The pump/motor is not a serviceable item; if it
requires replacement, the HCU must be replaced.
ABS FUSES
The ABS fuse and the ABS pump/motor fuse are
located in the power distribution center (PDC). Refer
to the sticker on the inside of the PDC cover for the
location of these fuses. The PDC is located on the
driver's side of the engine compartment between the
back of the battery and the brake master cylinder.
The CAB fuse can be found in the fuse junction
block under the instrument panel.
5 - 68 BRAKESPL
DESCRIPTION AND OPERATION (Continued)

ABS ELECTRONIC DIAGNOSIS
The following information is presented to give the
technician a general background on the diagnostic
capabilities of the ABS system. Complete electronic
diagnosis of the ABS system used on this vehicle is
covered in the Chassis Diagnostic Procedures manual.
Electronic diagnosis of the ABS system used on
this vehicle is performed using the DRBIIItscan
tool. The vehicle's scan tool diagnostic connector is
located under the steering column lower cover, to the
left side of the steering column (Fig. 10).
ABS SELF-DIAGNOSIS
The ABS system is equipped with a self-diagnosis
capability, which may be used to assist in the isola-
tion of ABS faults. The features are described below.
START-UP CYCLE
The self-diagnosis ABS start-up cycle begins when
the ignition switch is turned to the ON position.
Electrical checks are completed on ABS components,
including the CAB, solenoid continuity, and the relay
system operation. During this check the amber ABS
warning lamp is turned on for approximately 5 sec-
onds and the brake pedal may emit a popping sound,
moving slightly when the solenoid valves are
checked.
DRIVE-OFF CYCLE
The first time the vehicle is set in motion after an
ignition off/on cycle, the drive-off cycle occurs. This
cycle is performed when the vehicle reaches a speed
of approximately 20 kph (12 mph.).²The pump/motor is briefly activated to verify
function. When the pump/motor is briefly activated, a
whirling or buzzing sound may be heard by the
driver. This sound is normal, indicating the pump/
motor is running.
²The wheel speed sensor output correct operating
range is verified.
ONGOING TESTS
While the system is operating, these tests are per-
formed on a continuous basis:
²solenoid continuity
²wheel speed sensor continuity
²wheel speed sensor output
DIAGNOSTIC TROUBLE CODES (DTC's)
Diagnostic trouble codes (DTC's) are kept in the
controller's memory until either erased by the techni-
cian using the DRB, or erased automatically after
3500 miles or 255 ignition key cycles, whichever
occurs first. DTC's are retained by the controller
even if the ignition is turned off or the battery is dis-
connected. More than one DTC can be stored at a
time. When accessed, the number of occurrences
(ignition key cycles) and the DTC that is stored are
displayed. Most functions of the CAB and the ABS
system can be accessed by the technician for testing
and diagnostic purposes using the DRB.
LATCHING VERSUS NON-LATCHING DIAGNOSTIC TROUBLE
CODES
Some DTC's detected by the CAB are ªlatchingº
codes. The DTC is latched and ABS braking is dis-
abled until the ignition switch is reset. Thus, ABS
braking is non-operational even if the original DTC
has disappeared. Other DTC's are non-latching. Any
warning lamps that are turned on are only turned on
as long as the DTC condition exists; as soon as the
condition goes away, the amber ABS warning lamp is
turned off, although, in most cases, a DTC is set.
INTERMITTENT DIAGNOSTIC TROUBLE CODES
As with virtually any electronic system, intermit-
tent electrical problems in the ABS system may be
difficult to accurately diagnose. Most intermittent
electrical problems are caused by faulty electrical
connections or wiring. A visual inspection should be
done before trying to diagnose or service the antilock
brake system; this will eliminate unnecessary diag-
nosis and testing time. Perform a visual inspection
for loose, disconnected, damaged, or misrouted wires
or connectors; include the following components and
areas of the vehicle in the inspection.
(1) Inspect fuses in the power distribution center
(PDC) and the wiring junction block. Verify that all
fuses are fully inserted into the PDC and wiring
Fig. 10 ABS System Diagnostic Connector Location
1 ± DRIVER AIRBAG MODULE
2 ± PASSENGER AIRBAG MODULE
3 ± DATA LINK CONNECTOR
PLBRAKES 5 - 75
DIAGNOSIS AND TESTING (Continued)

junction block. A label on the underside of the PDC
cover identifies the locations of the ABS fuses.
(2) Inspect the 25-way electrical connector at the
CAB for damaged, spread, or backed-out wiring ter-
minals. Verify that the 25-way connector is fully
inserted in the socket of the CAB. Be sure that wires
are not stretched tight or pulled out of the connector.
(3) Verify that all the wheel speed sensor connec-
tions are secure.
(4) Look for poor mating of connector halves or ter-
minals not fully seated in the connector body.
(5)
Check for improperly formed or damaged termi-
nals. All connector terminals in a suspect circuit should
be carefully reformed to increase contact tension.
(6) Look for poor terminal-to-wire connections.
This requires removing the terminal from the connec-
tor body to inspect it.
(7) Verify pin presence in the connector assembly
(8) Check for proper ground connections. Check all
ground connections for signs of corrosion, loose fas-
teners, or other potential defects. Refer to the wiring
diagrams for ground locations.
(9) Look for problems with the main power sources
of the vehicle. Inspect the battery, generator, ignition
circuits and other related relays and fuses.
If a visual check does not find the cause of the
problem, operate the car in an attempt to duplicate
the condition and record any trouble codes.
Most failures of the ABS disable the ABS function
for the entire ignition cycle even if the fault clears
before key-off. There are some failure conditions,
however, that allow ABS operation to resume during
the ignition cycle in which the trouble occurred even
if the trouble conditions are no longer present.
The following trouble conditions may result in
intermittent illumination of the amber ABS warning
lamp.
²Low system voltage. If Low System Voltage is
detected by the CAB, the CAB will turn on the ABS
Warning Lamp until normal system voltage is
achieved. Once normal voltage is seen at the CAB,
normal operation resumes.
²High system voltage. If high system voltage is
detected by the CAB, the CAB will turn on the
Amber ABS Warning Lamp until normal system volt-
age is achieved. Once normal voltage is again
detected by the CAB, normal ABS operation resumes.
Additional possible causes that may result in the
illumination of the amber ABS warning lamp are as
follows:
²Any condition that interrupts electrical current
to the CAB may cause the amber ABS warning lamp
to turn on intermittently.
²If PCI communication between the body control-
ler and the CAB is interrupted, the body controller
can turn on the amber ABS warning lamp.
TONE WHEEL
Tone wheels can cause erratic wheel speed sensor
signals. Inspect tone wheels for the following possible
causes:
²missing, chipped, or broken teeth
²contact with the wheel speed sensor
²wheel speed sensor to tone wheel alignment
²wheel speed sensor to tone wheel clearance
²excessive tone wheel runout
²tone wheel loose on its mounting surface
If a front tone wheel is found to need replacement,
the drive shaft must be replaced. No attempt should
be made to replace just the tone wheel. Refer to the
DIFFERENTIAL AND DRIVELINE group in this
service manual for removal and installation.
If a rear tone wheel is found to need replacement,
the rear hub and bearing must be replaced. No
attempt should be made to replace just the tone
wheel. Refer to the SUSPENSION group in this ser-
vice manual for removal and installation.
If wheel speed sensor to tone wheel contact is evi-
dent, determine the cause and correct it before
replacing the wheel speed sensor or tone wheel.
Check the gap between the speed sensor head and
the tone wheel to ensure it is within specifications.
Refer to SPECIFICATIONS in this section of the ser-
vice manual for the minimum and maximum wheel
speed sensor to tone wheel clearance.
Excessive wheel speed sensor runout can cause
erratic wheel speed sensor signals. Refer to SPECI-
FICATIONS in this section of the service manual for
the maximum allowed tone wheel runout. If tone
wheel runout is excessive, determine if it is caused
by a defect in the driveshaft assembly or hub and
bearing. Replace as necessary.
Tone wheels are pressed onto their mounting sur-
faces and should not rotate independently from the
mounting surface. Replacement of the front drive-
shaft or rear hub and bearing is necessary.
BRAKE FLUID CONTAMINATION
Indications of fluid contamination are swollen or
deteriorated rubber parts. Swelling indicates the
presence of petroleum in the brake fluid.
To test for contamination, put a small amount of
drained brake fluid in clear glass jar. If the fluid sep-
arates into layers, there is mineral oil or other fluid
contamination of the brake fluid.
If the brake fluid is contaminated, drain and thor-
oughly flush the brake system. Replace all the rubber
parts or components containing rubber coming into
contact with the brake fluid including: the master
cylinder; proportioning valves; caliper seals; wheel
cylinder seals; ABS hydraulic control unit; and all
hydraulic fluid hoses.
5 - 76 BRAKESPL
DIAGNOSIS AND TESTING (Continued)

Radiator cooling fan control operation is accomplished
two ways. The fan always runs when the air condition-
ing compressor clutch is engaged. In addition to this
control, the fan is turned on by the temperature of the
coolant which is sensed by the coolant temperature sen-
sor which sends the message to the Powertrain Control
Module (PCM). The PCM turns on the fan through a
fan relay by grounding the relay's coil. The fan relay is
located in the Power Distribution Center (PDC) (Fig. 4).
Refer to the label beneath the PDC cover for location of
fan relay.
The PCM will actuate the fan relay whenever the A/C
clutch is engaged regardless of coolant temperature and
vehicle speed. If the A/C clutch is not engaged, the PCM
will actuate the fan relay when the coolant temperature
reaches approximately (97É C) 207É F and turns off the
fan relay when the coolant temperature drops to
approximately (94ÉC) 201É F. The fan relay is also
turned off when the vehicle speed is above approxi-
mately 100 Km/h (62 MPH). Refer to Group 8W, Wiring
Diagrams for circuity provided.
If the cooling fan is inoperative or a Diagnostic
Trouble Code (DTC) related to fan control has been
set, refer to the appropriate Powertrain Diagnostic
Manual for complete diagnostic procedures.
COOLING SYSTEM PRESSURE CAP
The cooling system pressure cap is located on the cool-
ant outlet housing near the front of the cylinder head.
The cooling system will operate at higher than atmo-
spheric pressure. The higher pressure raises the coolant
boiling point, allowing increased radiator cooling capac-
ity. The pressure cap will release cooling system pres-
sure in a range of 97±124 kPa (14±18 psi).
A vent valve located in the center of the cap allows
a small amount of coolant flow from the coolant
reserve system (CRS) tank. This valve is spring
loaded in the closed position. However, it must be
free to open during system cool-down.If the valve is
stuck shut, the radiator hoses will collapse on
cool-down. Clean the vent valve (Fig. 5) to
ensure proper sealing function.
There is a gasket in the cap that seals to the top of
the filler neck so that vacuum is maintained to draw
coolant back into the system from the coolant reserve
system (CRS) tank.
Fig. 4 Power Distribution Center (PDC)
RADIATOR COOLING FAN OPERATION CHART
Cooling Fan Control
A/C Off
Fan On: 97É C (207É F)
Fan Off: 94É C (201É F)Vehicle Speed >
100 Km/h (62
MPH)
A/C On
Fan OnÐregardless of coolant temperature or vehicle
speed.
Fig. 5 Cooling System Pressure Cap
1 ± PRESSURE RATING
2 ± FILLER NECK SEAL
3 ± PRESSURE VALVE
4 ± VACUUM VENT VALVE (SHOWN IN SEALING POSITION)
7 - 4 COOLING SYSTEMPL
DESCRIPTION AND OPERATION (Continued)

CONDITION POSSIBLE CAUSE CORRECTION
10. Air leak on the suction side of
water pump allows air to build up in
cooling system. This will cause the
thermostat to open late.10. Locate leak and repair as
necessary.
PRESSURE CAP IS BLOWING
OFF STEAM AND/OR COOLANT
FLOWING INTO RECOVERY
CONTAINER. TEMPERATURE
GAUGE READING MAY BE ABOVE
NORMAL, BUT NOT HIGH.
COOLANT LEVEL MAY BE HIGH
IN RECOVERY CONTAINER.1. Pressure relief valve in radiator
cap is defective.1. Check condition of radiator cap
and seals. Refer to Radiator Cap in
this section. Replace as necessary.
COOLANT LOSS TO THE
GROUND WITHOUT PRESSURE
CAP BLOWOFF. GAUGE IS
READING HIGH OR HOT.1. Coolant leaks in radiator, cooling
system hoses, water pump or
engine.1. Pressure test and repair as
necessary. Refer to Testing Cooling
System For Leaks in this section.
DETONATION OR PRE-IGNITION
(NOT CAUSED BY IGNITION
SYSTEM). GAUGE MAY OR MAY
NOT BE READING HIGH.1. Engine overheating. 1. Check reason for overheating
and repair as necessary.
2. Freeze point of coolant not
correct.2. Check the freeze point of the
coolant. Refer to Coolant
Concentration Testing in this
section. Adjust glycol-to-water ratio
as required.
HOSE OR HOSES COLLAPSE
WHEN ENGINE IS COOLING1. Vacuum created in cooling
system on engine cool-down is not
being relieved through coolant
recovery/reserve container system.1. (a) Radiator cap relief valve
stuck. Refer to Radiator Cap in this
section. Replace as necessary.
(b) Hose between coolant
recovery/reserve container and
radiator is kinked. Repair as
necessary.
(c) Vent at coolant recovery/reserve
container is plugged. Clean vent
and repair as necessary.
(d) Recovery/reserve container is
internally blocked or plugged. Check
for blockage and repair as
necessary.
ELECTRIC RADIATOR FAN
OPERATES ALL THE TIME.1. Fan relay, powertrain control
module (PCM) or engine coolant
temperature sensor defective.1. Refer to appropriate Powertrain
Diagnostic Procedures manual for
operation of the DRB scan tool.
Repair as necessary.
2. Check for low coolant level. 2. Repair as necessary.
7 - 10 COOLING SYSTEMPL
DIAGNOSIS AND TESTING (Continued)

CONDITION POSSIBLE CAUSE CORRECTION
ELECTRIC RADIATOR FAN WILL
NOT OPERATE. GAUGE READING
HIGH OR HOT1. Fan motor defective. 1. Refer to appropriate Powertrain
Diagnostic Procedures manual for
operation of the DRB scan tool.
Repair as necessary.
2. Fan relay, powertrain control
module (PCM) or engine coolant
temperature sensor defective.2. Refer to appropriate Powertrain
Diagnostic Procedures manual for
operation of the DRB scan tool.
Repair as necessary.
3. Blown fuse in power distribution
center (PDC).3. Determine reason for blown fuse
and repair as necessary.
NOISY FAN 1. Fan blade loose. 1. Replace fan blade assembly.
Refer to Cooling System Fan in this
section.
2. Fan blade striking a surrounding
object.2. Locate point of fan blade contact
and repair as necessary.
3. Air obstructions at radiator or A/C
condenser.3. Remove obstructions and/or
clean debris from radiator and/or
A/C condenser.
4. Electric fan motor defective. 4. Refer to procedure in this section.
INADEQUATE AIR CONDITIONER
PERFORMANCE (COOLING
SYSTEM SUSPECTED)1. Radiator and/or air conditioning
condenser is restricted, obstructed
or dirty.1. Remove restriction and/or clean
as necessary.
2. Electric radiator fan not operating
when A/C is on.2. Refer to appropriate Powertrain
Diagnostic Procedures manual for
operation of the DRB scan tool.
Repair as necessary.
3. Engine is overheating (heat may
be transferred from radiator to A/C
condenser). High underhood
temperature due to engine
overheating may also transfer heat
to A/C components.3. Correct overheating condition.
Refer to this section.
PLCOOLING SYSTEM 7 - 11
DIAGNOSIS AND TESTING (Continued)

STARTING SYSTEMS
TABLE OF CONTENTS
page page
GENERAL INFORMATION
INTRODUCTION..........................1
SUPPLY CIRCUIT AND CONTROL CIRCUIT.....1
DESCRIPTION AND OPERATION
STARTER MOTOR.........................1
DIAGNOSIS AND TESTING
CONTROL CIRCUIT........................2
FEED CIRCUIT RESISTANCE................3
FEED CIRCUIT...........................5STARTING SYSTEM.......................6
REMOVAL AND INSTALLATION
SAFETY SWITCHES.......................8
STARTER MOTOR.........................8
STARTER RELAY.........................8
SPECIFICATIONS
STARTER MOTOR.........................9
TORQUE................................9
GENERAL INFORMATION
INTRODUCTION
The starting system (Fig. 1) and (Fig. 2) has:
²Ignition switch
²Starter relay
²Park/Neutral Starting Back-Up Lamp Switch
with automatic transmissions
²Clutch Interlock/Upstop Switch with manual
transmissions
²Powertrain Control Module (PCM) for double
start over ride
²Wiring harness
²Battery
²Starter motor with an integral solenoid
These components form two separate circuits. A
high amperage circuit that feeds the starter motor up
to 300+ amps, and a control circuit that operates on
less than 20 amps.
The Powertrain Control Module (PCM) controls a
double start over ride safety that does not allow thestarter to be engaged if the engine is already run-
ning.
SUPPLY CIRCUIT AND CONTROL CIRCUIT
The starter system consists of two separate cir-
cuits:
²A high amperage supply to feed the starter
motor.
²A low amperage circuit to control the starter
solenoid.
DESCRIPTION AND OPERATION
STARTER MOTOR
The starter is a permanent magnet starter motor.
The fields have six permanent magnets. A planetary
gear train transmits power between starter motor
and pinion shaft. The starter provides mechanical
torque to rotate the crankshaft at an RPM (crank
speed) necessary for self-sustained spark/ignition.Fig. 1 Starting System Components - Automatic
Fig. 2 Starting System Components - Manual
PLSTARTING SYSTEMS 8B - 1

DIAGNOSIS AND TESTING
CONTROL CIRCUIT
The starter control circuit has:
²Starter solenoid
²Starter relay
²Park/Neutral Starting and Back-Up Lamp
Switch with automatic transmissions
²Clutch Interlock/Upstop Switch with manual
transmissions
²Ignition switch
²Battery
²All related wiring and connections
²Double Start Override algorithm located in the
PCM
CAUTION: Before performing any starter tests, the
ignition and fuel systems must be disabled.
²To disable ignition and fuel systems, disconnect
the Automatic Shutdown Relay (ASD). The ASD relay
is located in the in the Power Distribution Center
(PDC). Refer to the PDC cover for the proper relay
location.
STARTER SOLENOID
WARNING: CHECK TO ENSURE THAT THE TRANS-
MISSION IS IN THE PARK POSITION WITH THE
PARKING BRAKE APPLIED
(1) Verify battery condition. Battery must be in
good condition with a full charge before performing
any starter tests. Refer to Battery Tests.
(2) Perform Starter Solenoid test BEFORE per-
forming the starter relay test.
(3) Raise the vehicle.
(4) Perform a visual inspection of the starter/
starter solenoid for corrosion, loose connections or
faulty wiring.
(5) Lower the vehicle.
(6) Locate and remove the starter relay from the
Power Distribution Center (PDC). Refer to the PDC
label for relay identification and location.
(7) Connect a starter switch or a jumper wire
between the remote battery positive post and termi-
nal 87 of the starter relay connector.
(a) If engine cranks, starter motor and starter
solenoid is good. Go to the Starter Relay Test.(b) If engine does not crank or solenoid chatters,
check wiring and connectors from starter relay to
starter solenoid for loose or corroded connections.
Check for corroded connections at starter termi-
nals.
(c) Repeat test. If engine still fails to crank prop-
erly, trouble is within starter or starter mounted
solenoid, and replace starter.
STARTER RELAY
WARNING: CHECK TO ENSURE THAT THE TRANS-
MISSION IS IN THE PARK POSITION WITH THE
PARKING BRAKE APPLIED.
RELAY TEST
The starter relay is located in the Power Distribu-
tion Center (PDC) in the engine compartment. Refer
to the PDC label for relay identification and location.
Use the Starter Relay Pin Call-Out table and (Fig. 3)
for relay testing.
Remove the starter relay from the PDC as
described in this group to perform the following tests:
(1) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
no continuity between terminals 87 and 30. If OK, go
to Step 2. If not OK, replace the faulty relay.
(2) Resistance between terminals 85 and 86 (elec-
tromagnet) should be 7565 ohms. If OK, go to Step
3. If not OK, replace the faulty relay.
(3) Connect a battery B+ lead to terminals 86 and
a ground lead to terminal 85 to energize the relay.
The relay should click. Test for continuity between
terminals 30 and 87, and no continuity between ter-
minals 87A and 30. If OK, refer to Relay Circuit Test
procedure. If not OK, replace the faulty relay.
Fig. 3 Starter Relay
8B - 2 STARTING SYSTEMSPL

STARTER RELAY PIN CALL-OUT
PIN CIRCUIT COLOR DESCRIPTION
1 (86) A041 YL IGNITION SWITCH OUTPUT (START)
2 (85) K090 TN PCM
3 (30) A001 RD FUSED B+
4 (87A) NOT USED
5 (87) T040 BR STARTER SOLENOID
RELAY CIRCUIT TEST
(1) The relay common feed terminal cavity (30) is
connected to battery voltage and should be hot at all
times. If OK, go to Step 2. If not OK, repair the open
circuit to the PDC fuse as required.
(2) The relay normally closed terminal (87A) is
connected to terminal 30 in the de-energized position,
but is not used for this application. Go to Step 3.
(3) The relay normally open terminal (87) is con-
nected to the common feed terminal (30) in the ener-
gized position. This terminal supplies battery voltage
to the starter solenoid field coils. There should be
continuity between the cavity for relay terminal 87
and the starter solenoid terminal at all times. If OK,
go to Step 4. If not OK, repair the open circuit to the
starter solenoid as required.
(4) The coil battery terminal (86) is connected to
the electromagnet in the relay. It is energized when
the ignition switch is held in the START position. On
vehicles with a manual transmission, the clutch
pedal must be fully depressed for this test. Check for
battery voltage at the cavity for relay terminal 86
with the ignition switch in the START position, and
no voltage when the ignition switch is released to the
ON position. If OK, go to Step 5. If not OK with an
automatic transmission, check for an open or short
circuit to the ignition switch and repair, if required.
If the circuit to the ignition switch is OK, see the
Ignition Switch Test procedure in this group. If not
OK with a manual transmission, check the circuit
between the relay and the clutch interlock/upstop
switch for an open or a short circuit. If the circuit is
OK, refer to the Clutch Interlock/Upstop Switch
Diagnosis and Testing in Group 6-Clutch.
(5) The coil ground terminal (85) is connected to
the electromagnet in the relay. It is grounded
through the PCM only when the gearshift selector
lever is in the Park or Neutral positions. On vehicles
with a manual transmission, it is grounded through
the PCM when the clutch pedal is depressed. Check
for continuity to ground at the cavity for relay termi-
nal 85. If not OK, check for an open or short circuit
to the park/neutral starting and back-up lamp
switch, or the clutch interlock/upstop switch. Repair,
as necessary. If the circuit is OK, refer to the Park/Neutral Starting and Back-Up Lamp Switch Removal
and Installation in Group 21-Transaxle. Testing is
located within the Removal and Installation proce-
dures.
SAFETY SWITCHES
For diagnosis of:
²Clutch Interlock/Upstop Switch, refer to Diagno-
sis and Testing in Group 6-Clutch.
²Park/Neutral Starting and Back-Up Lamp
Switch, refer to Removal and Installation in Group
21-Transaxle. Testing is located within the Removal
and Installation procedures.
IGNITION SWITCH
After testing starter solenoid and relay, test igni-
tion switch and wiring. Check all wiring for opens or
shorts, and all connectors for being loose or corroded.
Refer to Group 8D-Ignition Systems, or Group
8W-Wiring Diagrams.
BATTERY
Refer to Group 8A-Battery for Diagnosis and Test-
ing of the battery.
ALL RELATED WIRING AND CONNECTORS
Refer to Group 8W-Wiring Diagrams.
FEED CIRCUIT RESISTANCE
Before proceeding with this operation, review Diag-
nostic Preparation and Starter Feed Circuit Tests.
The following operation will require a voltmeter,
accurate to 1/10 of a volt.
CAUTION: Ignition system also must be disabled to
prevent engine start while performing the following
tests.
(1) To disable the ignition and fuel systems, dis-
connect the Automatic Shutdown (ASD) Relay. The
ASD relay is located in the Power Distribution Cen-
ter (PDC). Refer to the PDC cover for proper relay
location.
(2) With all wiring harnesses and components
properly connected, perform the following:
PLSTARTING SYSTEMS 8B - 3
DIAGNOSIS AND TESTING (Continued)

FEED CIRCUIT
The following procedure will require a suitable
volt-ampere tester (Fig. 8).
CAUTION: Before performing any starter tests, the
ignition and fuel systems must be disabled.
(1) Connect a volt-ampere tester to the battery ter-
minals (Fig. 9). Refer to the operating instructions
provided with the tester being used.(2) To disable the ignition and fuel systems, dis-
connect the Automatic Shutdown (ASD) Relay. The
ASD relay is located in the Power Distribution Cen-
ter (PDC). Refer to the PDC cover for proper relay
location.
(3) Verify that all lights and accessories are OFF,
and the transmission shift selector is in the PARK
position or with the clutch pedal depressed and SET
parking brake.
CAUTION: Do not overheat the starter motor or
draw the battery voltage below 9.6 volts during
cranking operations.
(4) Rotate and hold the ignition switch in the
START position. Observe the volt-ampere tester (Fig.
8).
²If voltage reads above 9.6 volts, and amperage
draw reads above 280 amps, check for engine seizing
or faulty starter.
²If voltage reads 12.4 volts or greater and amper-
age reads 0 to 10 amps, check for corroded cables
and/or bad connections.
²If voltage is below 9.6 volts and amperage draw
is above 300 amps, the problem is the starter.
Replace the starter. Refer to Starter Removal and
Installation in this section.
(5) After the starting system problems have been
corrected, verify the battery state-of-charge and
charge battery if necessary. Disconnect all testing
equipment and connect the ASD relay. Start the vehi-
cle several times to assure the problem has been cor-
rected.
Fig. 7 Battery Positive Cable Resistance
1 ± VOLTMETER
Fig. 8 Volt Ampere Tester - Typical
Fig. 9 Volt-Ampere Tester Connections - Typical
1 ± POSITIVE CLAMP
2 ± NEGATIVE CLAMP
3 ± INDUCTION AMMETER CLAMP
PLSTARTING SYSTEMS 8B - 5
DIAGNOSIS AND TESTING (Continued)