DRIVE PLATE MISALIGNMENT
Common causes of misalignment are:
²Heat warping
²Mounting drive plate on a dirty crankshaft
flange
²Incorrect bolt tightening
²Improper seating on the crankshaft shoulder
²Loose crankshaft bolts
Clean the crankshaft flange before mounting the
drive plate. Dirt and grease on the flange surface
may misalign the flywheel, causing excessive runout.
Use new bolts when mounting drive plate to crank-
shaft. Tighten drive plate bolts to specified torque
only. Over-tightening can distort the drive plate hub
causing excessive runout.
CLUTCH CHATTER COMPLAINTS
For all clutch chatter complaints, do the following:
(1) Check for loose, misaligned, or broken engine
and transmission mounts. If present, they should be
corrected at this time. Test vehicle for chatter. If
chatter is gone, there is no need to go any further. If
chatter persists:
(2) Check to see if clutch cable routing is correct
and operates smoothly.
(3) Check for loose connections in drive train. Cor-
rect any problems and determine if clutch chatter
complaints have been satisfied. If not:
(4) Remove transaxle. See Group 21, Manual Tran-
saxle for procedure.
(5) Check to see if the release bearing is sticky or
binding. Replace bearing, if needed.
(6) Check linkage for excessive wear on the pivot
stud and fork fingers. Replace all worn parts.
(7) Check clutch assembly for contamination (dirt,
oil). Replace clutch assembly, if required.
(8) Check to see if the clutch disc hub splines are
damaged. Replace with new clutch assembly, if nec-
essary.
(9) Check input shaft splines for damage. Replace,
if necessary.
(10) Check for uneven wear on clutch fingers.
(11) Check for broken clutch cover diaphragm
spring fingers. Replace with new clutch assembly, if
necessary.
CLASH±INTO±REVERSE COMPLAINTS
Certain NV T350 (A-578) manual transaxles are
equipped with a reverse brake. It prevents clash
when shifting into reverse, but only if the vehicle is
not moving. See Group 21, Transaxle for further
diagnosis.
(1) Depress clutch pedal to floor and hold. After
three seconds, shift to reverse. If clash is present,
clutch has excessive spin time, and the reverse brake
may not be functioning.(2) Remove transaxle. See Group 21, Manual Tran-
saxle for procedure.
(3) Check the input shaft spline, clutch disc
splines, and release bearing for dry rust. If present,
clean rust off and apply a light coat of bearing grease
to the input shaft splines. Apply grease on the input
shaft splines only where the clutch disc slides. Verify
that the clutch disc slides freely along the input shaft
spline.
(4) Check to see if the clutch disc hub splines are
damaged, and replace with new clutch assembly if
required.
(5) Check the input shaft for damaged splines.
Replace as necessary.
(6) Check for broken clutch cover diaphragm
spring fingers.
(7) Install clutch assembly and transaxle.
CLUTCH INTERLOCK/UPSTOP SWITCH
The clutch interlock/upstop switch is an assembly
consisting of two switches: an engine starter inhibit
switch (clutch interlock) and a clutch pedal upstop
switch (Fig. 5). The switch assembly is located in the
clutch/brake pedal bracket assembly (Fig. 6), each
switch being fastened by four plastic wing tabs.
CLUTCH INTERLOCK SWITCH
Mechanical Test
(1) With the park brake set and the transaxleIN
NEUTRAL,turn the ignition key to the start posi-
tion. The engine starter should not crank with the
clutch pedal at rest (not depressed). If the starter
cranks, proceed to the electrical test to determine
whether the switch is defective or the circuit is
shorted. If the vehicle does not crank, proceed to the
next step.
(2) With the park brake set and the transaxleIN
NEUTRAL,fully depress the clutch pedal and turn
Fig. 5 Clutch Interlock/Upstop Switch
1 ± UPSTOP SWITCH
2 ± INTERLOCK SWITCH
3 ± CONNECTOR
PLCLUTCH 6 - 5
DIAGNOSIS AND TESTING (Continued)
the ignition key to the start position. The engine
starter should crank. If the starter does not crank,
visually inspect the clutch pedal for obstructions
(floor mat, etc.). Also make sure the clutch pedal
blade contacts and fully
Electrical Test
(1) Move ignition key to the ªOFF/LOCKº position
and remove key.
(2) Set park brake.
(3) Disconnect the clutch interlock/upstop switch
connector.
(4) Using an ohmmeter, check for continuity
between terminals2&3with the interlock switchnot depressed (clutch pedal at rest). There should be
no continuity between the terminals (open circuit).
(5) Fully depress the clutch pedal to close the
switch at least 1.25 mm (0.050 in.). The ohmmeter
should show continuity (0 ohms).
(6) If ohmmeter readings do not fall within these
ranges, the switch assembly is defective and should
be replaced. If the switch tests ok, wiring is defective.
Refer to Group 8W, Wiring Diagrams and repair
defective wiring.
UPSTOP SWITCH
Mechanical Test
(1) Raise vehicle on hoist.
(2) Start engine and operate speed control to main-
tain speed.
(3) Depress clutch pedal at least 33 mm (1.30 in.).
Speed control operation should terminate. If speed
control does not terminate, the upstop switch is
defective or the related wiring is shorted. Proceed to
the upstop switch electrical test.
Electrical Test
(1) Move ignition key to the ªOFF/LOCKº position
and remove key.
(2) Set park brake.
(3) Disconnect the clutch interlock/upstop switch
connector.
(4) Using an ohmmeter, check for continuity
between terminals1&2with the upstop switch
depressed (clutch pedal at rest). The ohmmeter
should show continuity (0 ohms).
(5) Depress the clutch pedal at least 33 mm (1.30
in.) check for continuity between terminals1&2.
There should be no continuity between the terminals
(open circuit).
(6) If ohmmeter readings do not fall within these
ranges, the switch assembly is defective and should
be replaced. If the switch tests ok, wiring is defective.
Refer to Group 8W, Wiring Diagrams and repair
defective wiring.
Fig. 6 Clutch/Brake Pedal Bracket Assembly
1 ± UPSTOP SWITCH
2 ± CLUTCH PEDAL
3 ± INTERLOCK SWITCH
4 ± CONNECTOR
6 - 6 CLUTCHPL
DIAGNOSIS AND TESTING (Continued)
SERVICE DIAGNOSIS±CLUTCH INTERLOCK/UPSTOP SWITCH
CONDITION POSSIBLE CAUSES CORRECTION
ENGINE STARTER
WON'T CRANK
WHEN CLUTCH
PEDAL IS
PRESSED TO THE
FLOORClutch interlock switch does not have
continuity when plunger is depressed 1.25
mm (1.30 in.)Defective switch or open wiring circuit.
Replace switch if necessary.
Interlock switch plunger is not depressed
when clutch pedal is pushed to the floorFloor mat interferes with clutch pedal
movement or clutch pedal bracket is bent.
Problem is related to other components in
the starting circuit.Check other components in the starting
circuit. Refer to Battery/Starting/Charging
System in Group 8.
SPEED CONTROL
DOES NOT
TERMINATE WHEN
CLUTCH PEDAL IS
DEPRESSED BY AT
LEAST 33 mm (1.30
in.)Upstop switch circuit is closed when clutch
pedal is depressed, or harness is shorted.Refer to Upstop Switch Electrical Test in
this group. Repair wiring or replace switch
assembly as necessary.
Other speed control system failure. Refer to Group 8H, Speed Control for
further diagnosis and testing procedures.
REMOVAL AND INSTALLATION
CLUTCH CABLE
REMOVAL
(1) Disconnect both battery cables.
(2) Remove battery clamp and remove battery
from vehicle.
(3) Remove battery tray from mount bracket.
(4) Remove bellhousing cap (Fig. 7).
(5) Disconnect clutch cable from transaxle housing
and clutch release lever as shown in (Fig. 7).
(6) Disconnect the clutch cable from the clutch
pedal spacer (Fig. 8).
NOTE: Use care when handling clutch cable
assembly. Improper handling can cause adjuster
mechanism to come apart, making re-installation
difficult.
(7) Carefully guide cable through pedal assembly
bore and remove from vehicle.
INSTALLATION
(1) Insert the clutch pedal end of the cable into
position and connect the cable to the clutch pedal
spacer as shown in (Fig. 8).
(2) Verify adjuster mechanism function as follows:
(a) With slight pressure, pull the clutch release
lever end of the cable to draw the cable taut.(b) Push the clutch cable housing toward the
dash panel (With less than 25 lbs. of effort, the
cable housing should move 30-50mm.). If the cable
Fig. 7 Clutch Cable at Transaxle
1 ± CLUTCH CABLE
2 ± TRANSAXLE
3 ± BELLHOUSING CAP
PLCLUTCH 6 - 7
DIAGNOSIS AND TESTING (Continued)
CONDITION POSSIBLE CAUSE CORRECTION
16. Electric cooling fan not
operating properly.16. Check electric fan operation and
repair as necessary.
17. Cylinder head gasket leaking. 17. Check cylinder head gasket for
leaks. Refer to testing cooling
system for leaks. For repairs, refer
to Group 9, Engine.
18. Heater core leaking. 18. Check heater core for leaks.
Refer to Group 24, Heating and Air
Conditioning and repair as
necessary.
TEMPERATURE GAUGE READING
IS INCONSISTENT (FLUCTUATES,
CYCLES OR IS ERRATIC)1. The gauge may cycle up and
down. This is due to the cycling of
the electric radiator fan.1. A normal condition. No correction
is necessary. If gauge cycling is
going into the hot zone, check
electric fan operation and repair as
necessary. Refer to procedure in
this section.
2. During cold weather operation
with the heater blower in the high
position, the gauge reading may
drop slightly.2. A normal condition. No correction
is necessary.
3, Temperature gauge or engine
mounted gauge sensor is defective
or shorted.3. Check operation of gauge and
repair as necessary. Refer to Group
8E, Instrument Panel and Gauges.
4. Gauge reading rises when
vehicle is brought to a stop after
heavy use (engine still running).4. A normal condition. No correction
is necessary. The gauge should
return to normal range after vehicle
is driven.
5. Gauge reading high after
restarting a warmed-up (hot)
engine.5. A normal condition. No correction
is necessary. The gauge should
return to normal range after a few
minutes of engine operation.
6. Coolant level low in radiator (air
will build up in the cooling system
causing the thermostat to open
late).6. Check and correct coolant leaks.
Refer to Testing Cooling System For
Leaks in the section.
7. Cylinder head gasket leaking
allowing exhaust gas to enter
cooling system. This will cause
thermostat to open late.7. (a) Check for cylinder head
gasket leaks with a commercially
available Block Leak Tester. Repair
as necessary.
(b) Check for coolant in the engine
oil. Inspect for white steam emitting
from exhaust system. Repair as
necessary.
8. Water pump impeller loose on
shaft.8. Check water pump and replace
as necessary. Refer to Water Pump
in this section.
9. Loose drive belt (water pump
slipping).9. Check drive belt and correct as
necessary.
PLCOOLING SYSTEM 7 - 9
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)
STARTING SYSTEM
For circuit descriptions and diagrams, refer to
8W-21, Starting System in Group 8W-Wiring Dia-
grams.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, REFER TO GROUP 8M - PASSIVE
RESTRAINT SYSTEMS BEFORE ATTEMPTING
STEERING WHEEL, STEERING COLUMN, OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
INSPECTION
Before removing any unit from the starting system
for repair or diagnosis, perform the following inspec-
tions:
²Battery- Visually inspect the battery for indi-
cations of physical damage and loose or corroded
cable connections. Determine the state-of-charge and
cranking capacity of the battery. Charge or replace
the battery, if required. Refer to Group 8A-Battery
for more information.²Ignition Switch- Visually inspect the ignition
switch for indications of physical damage and loose
or corroded wire harness connections.
²Clutch Interlock/Upstop Switch- Visually
inspect the clutch interlock/upstop switch for indica-
tions of physical damage and loose or corroded wire
harness connections.
²Park/Neutral Starting and Back-Up Lamp
Switch- Visually inspect the park/neutral starting
and back-up lamp switch for indications of physical
damage and loose or corroded wire harness connec-
tions.
²Starter Relay- Visually inspect the starter
relay for indications of physical damage and loose or
corroded wire harness connections.
²Starter Motor- Visually inspect the starter
motorfor indications of physical damage and loose or
corroded wire harness connections.
²Starter Solenoid- Visually inspect the starter
solenoid for indications of physical damage and loose
or corroded wire harness connections.
²Wiring- Visually inspect the wire harness for
damage. Repair or replace any faulty wiring, as
required.
8B - 6 STARTING SYSTEMSPL
DIAGNOSIS AND TESTING (Continued)