1998 ISUZU TROOPER horn

SUPPLEMENTAL RESTRAINT SYSTEM STEERING WHEEL & COLUMN 2A – 57
STEERING WHEEL REPLACEMENT
1
3
2
4
Removal Steps
1. Inflator module
2. Horn lead
3. Steering wheel fixing nut
4. Steering wheel
Installation Steps
4. Steering wheel
3. Steering wheel fixing nut
2. Horn lead
1. Inflator module
430RS016
These steps are based on the LHD model.
REMOVAL
Preparation:
1) Turn the steering wheel so that the vehicle's wheels
are pointing straight ahead.
2) Turn the ignition switch to "LOCK".
3) Disconnect the battery ground cable, and wait at least
5 minutes.
4) Disconnect the yellow 2way SRS connector located
under the steering column. CAUTION:
Once the steering column is removed from the vehicle, the column is extremely suspectible to
damage. Dropping the column assembly on its end could collapse the steering shaft or loosen the
slide block which maintains column rigidity. Leaning on the column assembly could cause the jacket
to bend or deform. Any of the above damage could impair the column's collapsible design. If it is
necessary to remove the steering wheel, use only the specified steering wheel puller. Under no
conditions should the end of the shaft be hammered upon, as hammering could loosen slide block
which maintains column rigidity.

2A – 58 SUPPLEMENTAL RESTRAINT SYSTEM STEERING WHEEL & COLUMN
1. Inflator Module
1) Loosen the inflator module fixing bolt from
behind the steering wheel assembly using a
TORX
driver or equivalent until the inflator
module can be released from steering assembly.
2) Disconnect the yellow 2way SRS connector
located behind the inflator module.
WARNING
THE INFLATOR MODULE SHOULD ALWAYS BE CARRIED
WITH THE URETHANE COVER AWAY FROM YOUR BODY
AND SHOULD ALWAYS BE LAID ON A FLAT SURFACE
WITH THE URETHANE SIDE UP. THIS IS NECESSARY
BECAUSE A FREE SPACE IS PROVIDED TO ALLOW THE
AIR CUSHION TO EXPAND IN THE UNLIKELY EVENT OF
ACCIDENTAL DEPLOYMENT. OTHERWISE, PERSONAL
INJURY MAY RESULT.
2. Horn Lead
3. Steering Wheel Fixing Nut
4. Steering Wheel
1) Apply a setting mark across the steering wheel
and shaft so parts can be reassembled in their
original position.
2) Move the front wheels to the straight ahead
position and use special tool.
Steering wheel remover: 5-8840-0016-0 (J-29752)
NOTE:
Never apply force to the steering wheel in direction
of the shaft by using a hammer or other impact tools
in an attempt to remove the steering wheel. The
steering shaft is designed as an energy absorbing
unit.
827RS014
827RS016
430RS004
Up
Setting mark

SUPPLEMENTAL RESTRAINT SYSTEM STEERING WHEEL & COLUMN 2A Ð 59
INSTALLATION
4. Steering Wheel
Align the setting marks made when removing.
CAUTION:
Never apply force to the setting wheel in direction of the
shaft by using a hammer or other impact tools in an
attempt to install the steering wheel. The setting shaft is
designed as an energy absorbing unit.
3. Steering Wheel Fixing Nut
Steering Wheel Nut Torque Nám (kgám/lbáft)
34 (3.5 / 25)
2. Horn Lead
1. Inflator Module
1) Support the module and carefully connect the
module connector.
CAUTION:
·Never use the air bag assembly from another vehicle.
Use only the air bag assembly for "UBS".
·When replace the inflator module, use only same parts
number assembly. If different parts number assembly is
installed, the air bag system can not function correctly
because it has different characteristic.
NOTE:
Pass the lead wire through the tabs on the plastic
cover (wire protector) of inflator to prevent lead wire
from being pinches.
2) Secure the module with one bolt to relieve
weight on the connector wire.
3) Tighten bolts to specified sequence as figure.
Inflator module Bolt Torque Nám (kgám/lbáin)
8 (0.8 / 69)
4) Connect the yellow 2way SRS connector located
under the steering column.
5) Connect the battery ground cable.
6) Set ignition to "ON" while watching warning
light. Light should flash 7 times and then go off.
If lamp does not operate correctly, refer to
Section 9J.
3
41
2
827RS017

6E±74
ENGINE DRIVEABILITY AND EMISSIONS
No Malfunction Indicator Lamp (MIL)
D06RW00006
Circuit Description
The ªCheck Engineº lamp (MIL) should always be
illuminated and steady with the ignition ªONº and the
engine stopped. Ignition feed voltage is supplied to the
MIL bulb through the meter fuse. The powertrain control
module (PCM) turns the MIL ªONº by grounding the MIL
driver circuit.
Diagnostic Aids
An intermittent MIL may be cased by a poor connection,
rubbed-through wire insulation, or a wire broken inside
the insulation. Check for the following items:

Inspect the PCM harness and connections for
improper mating, broken locks, improperly formed or
damaged terminals, poor terminal-to-wire connection,
and damaged harness.

If the engine runs OK, check for a faulty light bulb, an
open in the MIL driver circuit, or an open in the
instrument cluster ignition feed.
If the engine cranks but will not run, check for an open
PCM ignition or battery feed, or a poor PCM to engine
ground.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. A ªNo MILº condition accompanied by a no-start
condition suggests a faulty PCM ignition feed or
battery feed circuit.
9. Using a test light connected to B+, probe each of the
PCM ground terminals to ensure that a good ground
is present. Refer to
PCM Terminal End View for
terminal locations of the PCM ground circuits.
12.In this step, temporarily substitute a known good
relay for the PCM relay. The horn relay is nearby,
and it can be verified as ªgoodº simply by honking
the horn. Replace the horn relay after completing
this step.

6E±87 ENGINE DRIVEABILITY AND EMISSIONS
Fuel System Electrical Test

 
StepNo Ye s Value(s) Action
9Check for short or open between the PCM and the fuel
pump relay.
Was a problem found?
ÐVerify repairGo to Step 10
101. Check the fuel pump relay circuit for a poor terminal
connection at the PCM.
2. If a problem is found, replace terminal as necessary.
Was a problem found?
ÐVerify repairGo to Step 11
11Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
UBS 98model year Immobilizer
Workshop Manual.
Is the action complete?ÐVerify repairÐ
121. Reconnect the fuel pump relay.
2. Disconnect the fuel pump electrical connector at the
fuel tank.
3. Using a test light connected to ground, probe the
fuel pump feed wire (harness side).
4. Command the fuel pump ªONº with Tech 2.
Did the light illuminate for 2 seconds?
ÐGo to Step 15Go to Step 13
131. Honk the horn to verify that the horn relay is
functioning.
2. Substitute the horn relay for the fuel pump relay.
3. Leave the test light connected as in step 12.
4. Command the fuel pump ªONº with Tech 2.
Did the test light illuminate for 2 seconds when the fuel
pump was commanded ªON?º
ÐGo to Step 17Go to Step 14
141. Re-connect the horn relay in its proper location.
2. Check for a short circuit, blown fuse or open circuit
between the relay and the fuel tank.
Is the action complete?
ÐVerify repairÐ
151. With the fuel pump electrical connector at the fuel
tank disconnected, connect a test light between the
feed wire and the ground wire (harness side).
2. Command the fuel pump ªONº with Tech 2.
Did the test light illuminate for 2 seconds?
ÐGo to Step 18Go to Step 16
16Repair the open circuit in the fuel pump ground wire.
Is the action complete?
ÐVerify repairÐ
171. Re-connect the horn relay in its proper location.
2. Replace the fuel pump relay.
Is the action complete?
ÐVerify repairÐ
18Replace the fuel pump.
Is the action complete?
ÐVerify repairÐ

6E±323 ENGINE DRIVEABILITY AND EMISSIONS
11. Connect the fuel filler fuse at the tank.
12. Connect the air breather hose at the tank.
TS23796
13. Fill the fuel tank with fuel.
14. Tighten the fuel filler cap.
15. Connect the negative battery cable.
Throttle Body (TB)
Removal Procedure
1. Disconnect the negative battery cable.
2. Drain the cooling system. Refer to
Cooling System.
3. Remove the accelerator cable assembly. Refer to
Accelerator Cable in Engine Speed Control System..
4. Disconnect the electrical connectors:

Throttle position (TP) sensor.

Idle air control (IAC) solenoid.

Intake air temperature (IAT) sensor. Refer to
Intake Air Temperature Sensor.
035RW023
5. Disconnect the vacuum hose below the air horn.
6. Remove the intake air duct clamp.
7. Disconnect the intake air duct.
8. Disconnect the coolant lines from the throttle body.
9. Remove the bolts from the common chamber.
10. Remove the throttle body from the common chamber.
11. Remove the gasket from the upper intake manifold.
035RW024
12. Remove the IAC. Refer to Idle Air Control (IAC)
Solenoid
.
13. Remove the TP sensor. Refer to
Throttle Position
(TP) Sensor
.
Inspection Procedure
NOTE: Do not use solvent of any type when you clean the
gasket surfaces on the intake manifold and the throttle
body assembly. The gasket surfaces and the throttle
body assembly may be damaged as a result.

If the throttle body gasket needs to be replaced,
remove any gasket material that may be stuck to the
mating surfaces of the manifold.

Do not leave any scratches in the aluminum casting.
Installation Procedure
1. Install the TP sensor. Refer to Throttle Position (TP)
Sensor
.
2. Install the IAC. Refer to
Idle Air Control (IAC)
Solenoid
.
3. Install the gasket on the common chamber.
4. Install the throttle body on the common chamber.

6E±44
4JX1±TC ENGINE DRIVEABILITY AND EMISSIONS
No Malfunction Indicator Lamp (MIL)
060RW136
Circuit Description
The ªCheck Engineº lamp (MIL) should always be
illuminated and steady with the ignition ªONº and the
engine stopped. Ignition feed voltage is supplied to the
MIL bulb through the meter fuse. The Engine Control
Module ECM turns the MIL ªONº by grounding the MIL
driver circuit.
Diagnostic Aids
An intermittent MIL may be cause by a poor connection,
rubbed-through wire insulation, or a wire broken inside
the insulation. Check for the following items:

Inspect the ECM harness and connections for
improper mating, broken locks, improperly formed or
damaged terminals, poor terminal-to-wire
connection, and damaged harness.

If the engine runs OK, check for a faulty light bulb, an
open in the MIL driver circuit, or an open in the
instrument cluster ignition feed.
If the engine cranks but will not run, check for an open
ECM ignition or battery feed, or a poor ECM to engine
ground.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. A ªNo MILº condition accompanied by a no-start
condition suggests a faulty ECM ignition feed or
battery feed circuit.
9. Using a test light connected to B+, probe each of the
ECM ground terminals to ensure that a good ground
is present. Refer to
ECM Terminal End View for
terminal locations of the ECM ground circuits.
12.In this step, temporarily substitute a known good
relay for the ECM relay. The horn relay is nearby,
and it can be verified as ªgoodº simply by honking
the horn. Replace the horn relay after completing
this step.

WIRING SYSTEM 8DÐ1
BODY AND ACCESSORIES
WIRING SYSTEM
CONTENTS
Service Precautions . . . . . . . . . . . . . . . . . . . 8DÐ3
General Description . . . . . . . . . . . . . . . . . . . 8DÐ4Notes for Working on Electrical Items . . 8DÐ4
Symbols and Abbreviations . . . . . . . . . . . 8DÐ10
Parts for Electrical Circuit . . . . . . . . . . . . . 8DÐ12
Reading the Circuit Diagram . . . . . . . . . . 8DÐ21
Main Data and Specifications . . . . . . . . . . . 8DÐ24 Fuse, Fusible Link and Circuit Breaker Location . . . . . . . . . . . . . . . . . . . . . . . . . . . 8DÐ24
Relay Location . . . . . . . . . . . . . . . . . . . . . . 8DÐ27
Diode Location . . . . . . . . . . . . . . . . . . . . . . 8DÐ30
Grounding Point . . . . . . . . . . . . . . . . . . . . . 8DÐ33
Cable Harness Routing . . . . . . . . . . . . . . . 8DÐ45
Fuse Block Circuit . . . . . . . . . . . . . . . . . . . . . 8DÐ53 Circuit Diagram. . . . . . . . . . . . . . . . . . . . . . 8DÐ54
Start and Charging . . . . . . . . . . . . . . . . . . . . 8DÐ67 General Description . . . . . . . . . . . . . . . . . . 8DÐ67
Circuit Diagram. . . . . . . . . . . . . . . . . . . . . . 8DÐ68
Parts Location . . . . . . . . . . . . . . . . . . . . . . . 8DÐ70
Powertrain Control Module (PCM) . . . . . . . 8DÐ80 General Description . . . . . . . . . . . . . . . . . . 8DÐ80
Circuit Diagram. . . . . . . . . . . . . . . . . . . . . . 8DÐ81
Parts Location . . . . . . . . . . . . . . . . . . . . . . . 8DÐ93
QOSIII (4JG2) . . . . . . . . . . . . . . . . . . . . . . . . . 8DÐ111 General Description . . . . . . . . . . . . . . . . . . 8DÐ111
Circuit Diagram. . . . . . . . . . . . . . . . . . . . . . 8DÐ112
Parts Location . . . . . . . . . . . . . . . . . . . . . . . 8DÐ114
QOS and EGR System (4JG2) . . . . . . . . . . . 8DÐ118 General Description . . . . . . . . . . . . . . . . . . 8DÐ118
Circuit Diagram. . . . . . . . . . . . . . . . . . . . . . 8DÐ119
Parts Location . . . . . . . . . . . . . . . . . . . . . . . 8DÐ122
Headlight and Fog Light . . . . . . . . . . . . . . . . 8DÐ127 General Description . . . . . . . . . . . . . . . . . . 8DÐ127
Circuit Diagram. . . . . . . . . . . . . . . . . . . . . . 8DÐ128
Parts Location . . . . . . . . . . . . . . . . . . . . . . . 8DÐ130
Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . 8DÐ134
Rear Foglight . . . . . . . . . . . . . . . . . . . . . . . . . 8DÐ150 Circuit Diagram. . . . . . . . . . . . . . . . . . . . . . 8DÐ151
Parts Location . . . . . . . . . . . . . . . . . . . . . . . 8DÐ152
Headlight Leveling . . . . . . . . . . . . . . . . . . . . 8DÐ153 General Description . . . . . . . . . . . . . . . . . . 8DÐ153
Circuit Diagram. . . . . . . . . . . . . . . . . . . . . . 8DÐ154
Parts Location . . . . . . . . . . . . . . . . . . . . . . . 8DÐ155
Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . 8DÐ156
Clearance Light, Taillight and License Plate Light . . . . . . . . . . . . . . . . . . . . 8DÐ159 General Description . . . . . . . . . . . . . . . . . . 8DÐ159
Circuit Diagram. . . . . . . . . . . . . . . . . . . . . . 8DÐ160
Parts Location . . . . . . . . . . . . . . . . . . . . . . . 8DÐ163
Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . 8DÐ168
Interior Illumination Light . . . . . . . . . . . . . . 8DÐ180 General Description . . . . . . . . . . . . . . . . . . 8DÐ180
Circuit Diagram. . . . . . . . . . . . . . . . . . . . . . 8DÐ181
Parts Location . . . . . . . . . . . . . . . . . . . . . . . 8DÐ185
Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . 8DÐ192
Turn Signal Light and Hazard Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8DÐ193
General Description . . . . . . . . . . . . . . . . . . 8DÐ193
Circuit Diagram. . . . . . . . . . . . . . . . . . . . . . 8DÐ194
Parts Location . . . . . . . . . . . . . . . . . . . . . . . 8DÐ197
Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . 8DÐ202
Stoplight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8DÐ208 General Description . . . . . . . . . . . . . . . . . . 8DÐ208
Circuit Diagram. . . . . . . . . . . . . . . . . . . . . . 8DÐ209
Parts Location . . . . . . . . . . . . . . . . . . . . . . . 8DÐ212
Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . 8DÐ216
Backup Light. . . . . . . . . . . . . . . . . . . . . . . . . . 8DÐ220 General Description . . . . . . . . . . . . . . . . . . 8DÐ220
Circuit Diagram. . . . . . . . . . . . . . . . . . . . . . 8DÐ221
Parts Location . . . . . . . . . . . . . . . . . . . . . . . 8DÐ223
Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . 8DÐ227
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8DÐ230 General Description . . . . . . . . . . . . . . . . . . 8DÐ230
Circuit Diagram. . . . . . . . . . . . . . . . . . . . . . 8DÐ231
Parts Location . . . . . . . . . . . . . . . . . . . . . . . 8DÐ232
Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . 8DÐ235
Dome Light, Luggage Room Light, Courtesy Light and Map Light . . . . . . . . . . 8DÐ237
General Description . . . . . . . . . . . . . . . . . . 8DÐ237
Circuit Diagram. . . . . . . . . . . . . . . . . . . . . . 8DÐ238
Parts Location . . . . . . . . . . . . . . . . . . . . . . . 8DÐ240
Power Door Lock . . . . . . . . . . . . . . . . . . . . . . 8DÐ244 General Description . . . . . . . . . . . . . . . . . . 8DÐ244
Circuit Diagram. . . . . . . . . . . . . . . . . . . . . . 8DÐ245
Parts Location . . . . . . . . . . . . . . . . . . . . . . . 8DÐ250
Diagnosi s. . . . . . . . . . . . . . . . . . . . . . . . . . . 8DÐ2 56
Power Window . . . . . . . . . . . . . . . . . . . . . . . 8DÐ261 General Description . . . . . . . . . . . . . . . . . . 8DÐ261
Circuit Diagram. . . . . . . . . . . . . . . . . . . . . . 8DÐ262
Parts Location . . . . . . . . . . . . . . . . . . . . . . . 8DÐ263
Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . 8DÐ266
Cruise Control . . . . . . . . . . . . . . . . . . . . . . . . 8DÐ272