CIRCUIT DIAGRAM ISUZU TROOPER 1998 Service Repair Manual

SERVICE INFORMATION 00 Ð 3
TROUBLESHOOTING
CONTENTS
PAGE
Circuit Diagram.........................................................00Ð 4
Heating Cycle Troubleshooting............................................00Ð16
Fan Control Knob (Fan Switch)............................................00Ð17
Blower Motor Does Not Run............................................00Ð18
Blower Motor Does Not Run In Certain Position............................00Ð19
Blower Motor Does Not Stop at ÒOFFÓ Position............................00Ð19
Ceramic Heater.........................................................00Ð20
Ceramic Heater Does Not Operate.......................................00Ð21
Ceramic Heater Does Not Stop..........................................00Ð22
Air Conditioning Cycle Troubleshooting.....................................00Ð23
Checking Refrigerant System with Manifold Gauge.........................00Ð24
Magnetic Clutch........................................................00Ð27
6VD1/6VE1 Engine....................................................00Ð27
4JG2 Engine.........................................................00Ð31
4JX1 Engine..........................................................00Ð34
Condenser Fan..........................................................00Ð37
Condenser Fan Does Not Run...........................................00Ð38
Condenser Fan Does Not Stop..........................................00Ð39
Compressor Troubleshooting.............................................00Ð40
Individual Inspection.....................................................00Ð41

00 Ð 4 SERVICE INFORMATION
CIRCUIT DIAGRAM
6VD1/6VE1 (RHD)
0.5 LG
0.5 LG
B -1 BODY-RH
BODY-LH
FRAME
ENG.5B
BODY
8B / R
8 B
+
_
P - 6
30B
P - 1
P - 5
P - 10
P - 7
P - 2
FL-1
80A MAINFL-4
30A CONDENSER FAN
F-6
15A RR COOLER
I-232
I-236 A/C SW
BLOWER
MOTOR
0.3 G/Y
I-42 I-42
I-421 3
216
0.5 LG
1
5W
B-190.5 BR
0.5 BR
0.5 P/G H-24 H-5113 1
H-167
H-16
2 L/R
I-41
I-18
I-18
I-18
I-18 1.25 L/O
1.25 L/Y
0.85 L/W 3
36
5
2 4
1 6
FAN SW HEATER BEZEL
ILLUMINATION
I-23 I-23
I-18
I-183
5
4
10.3 R/G0.85 G/R
ILLUMINATION
CONTROLLER (3) RELAY ; TAIL (4)
H-201
2 B
2BLOWER
RESISTOR
I-41
I-41
I-41
I-41
2L/B
2 B
1.25B
M
B-52
1B-5
B-361
B-36
B-36 B-362
34
I-23
10.85W/G
3L/R 3LC-19
25A BLOWER
0.3B
ELECTRONIC
THERMOSTAT
5W 3W
0.5 BR
1.25 L/O
0.5 LG/Y
0.3 G/Y 0.3 G/Y RELAY ;
HEATER AND
A/C
C-20 10A
AIR CON.
0.5 BR 0.5 BR
RELAY;STARTER (1)
5W
H-14
16
H-26
2L/B
2
H-20
H-1310
0.3 G/Y
0.5 LG
D08RY00128

1B Ð 2 AIR CONDITIONING
Full Automatic Air Conditioning System....................................1BÐ 60
General Description.....................................................1BÐ 60
Full Automatic Air Conditioner Part Configuration.........................1BÐ 60
Circuit Diagram......................................................1BÐ 62
Function and Features.................................................1BÐ 74
Full Automatic Air Conditioner Block Diagram.............................1BÐ 75
Air Conditioning Parts.................................................1BÐ 76
Control Panel Layout..................................................1BÐ 80
Air Control Functions.................................................1BÐ 81
Operation and Function of Control Panel Switches.........................1BÐ 82
Overview of Construction, Movement and Control of Major Parts of Full Automatic
Air Conditioner System................................................1BÐ 84
Overview of Automatic Control of Full Automatic Air Conditioner............1BÐ 88
Troubleshooting........................................................1BÐ 92
Troubleshooting, Its Overview and Procedures............................1BÐ 92
Performance and Movement Checklist for Automatic Air Conditioner Related
Parts...............................................................1BÐ 95
Troubleshooting with Self-Diagnosis Function............................1BÐ 97
Inspection by Failed Location.............................................1BÐ100
Inspection of the Sensors..............................................1BÐ100
Inspection of the Intake Actuator System.................................1BÐ104
Inspection of the Mix Actuator System...................................1BÐ107
Inspection of the Mode Actuator System.................................1BÐ110
Inspection of the Fan Motor System.....................................1BÐ113
Inspection of the Magnet Clutch System.................................1BÐ118
Inspection of the Air Conditioner Room Temperature Setup System..........1BÐ123
Individual Inspection..................................................1BÐ124
On-Vehicle Service......................................................1BÐ126
Power Transistor.....................................................1BÐ126
Automatic Air Conditioner Control Unit..................................1BÐ126
In Car Sensor........................................................1BÐ127
Ambient Sensor......................................................1BÐ127
Sun Sensor..........................................................1BÐ128
Electronic Thermostat.................................................1BÐ128
Mode Actuator.......................................................1BÐ129
Mix Actuator.........................................................1BÐ129
Intake Actuator......................................................1BÐ130

1BÐ62 AIR CONDITIONING
CIRCUIT DIAGRAM
6VE1 (RHD)
B-5
BLOWER
MOTOR2
B-5
1
I-51
3I-51
I-51I-51
MAX HI
RELAY POWER
TRANSISTORI-50
I-50
4
H-202
H-26
10
1
3
H-20
121 2L/B
0.5P/G
12
I-32
16 I-32
P-2
0.85W/G5W
5W 0.5R/W
0.3B0.5R/W 0.3R/W
TAIL RELAY(4) ILLUMINATION
CONTROLLER0.5G/R 0.85G/R
1.25B
1.25B1.25B
0.5B
9 I-32 5W 3W
BATT
FL-1
80A
MAIN4B-36
33L/R
C-19 25A
BLOWERC-20 10A
AIR CON
3L 2L/B
0.3BR
0.5BR0.3BR 2/B 0.3GR
0.3GR/L0.5L/B
2/B
B-36
20
H-27 2
B-36H-14
1
B-36HEATER & A/C RELAY
STARTER RELAY(1)
H-141
H-1310
I-328
H-269
10 C-16
10A CLOCK ROOM
BODY-RHBODY-LH
B-18
B-19
B-1
AUTO A/C CONTROL UNITAUTO A/C CONTROL UNIT
I-3217
14 35 2112 337
I-32
22
29 6I-331 H-20
14
H-16
M
192B
I-33
2I-50
D08RY00118

4B2±1 DRIVE LINE CONTROL SYSTEM (TOD)
DRIVELINE/AXLE
DRIVELINE CONTROL SYSTEM (TOD)
CONTENTS
Service Precaution 4B2±1. . . . . . . . . . . . . . . . . . . . . .
General Description 4B2±2. . . . . . . . . . . . . . . . . . . . .
System Components 4B2±4. . . . . . . . . . . . . . . . . . . .
Parts Location 4B2±4. . . . . . . . . . . . . . . . . . . . . . . .
Functions of Indicator Lamp 4B2±8. . . . . . . . . . . . . .
Diagnosis 4B2±12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Basic Diagnostic Flow Chart 4B2±16. . . . . . . . . . . . . .
Parts Location 4B2±17. . . . . . . . . . . . . . . . . . . . . . . . . .
Circuit Diagram 4B2±18. . . . . . . . . . . . . . . . . . . . . . . . . Connector List 4B2±21. . . . . . . . . . . . . . . . . . . . . . . . . .
Checking Failed Pin 4B2±23. . . . . . . . . . . . . . . . . . . . .
Checking Failed TOD Control Unit Pin 4B2±26. . . . .
Diagnostic Trouble Codes 4B2±30. . . . . . . . . . . . . . . .
Diagnosis from Trouble Codes 4B2±31. . . . . . . . . . . .
Trouble Diagnosis Depending on The Status
of TOD Indicator 4B2±58. . . . . . . . . . . . . . . . . . . . . . . .
Diagnosis from Symptom 4B2±86. . . . . . . . . . . . . . . . .
Service Precaution
WARNING: I F S O E Q U IPPED WITH A
SUPPLEMENTAL RESTRAINT SYSTEM (SRS),
REFER TO THE SRS COMPONENT AND WIRING
LOCATION VIEW IN ORDER TO DETERMINE
WHETHER YOU ARE PERFORMING SERVICE ON OR
NEAR THE SRS COMPONENTS OR THE SRS
WIRING. WHEN YOU ARE PERFORMING SERVICE
ON OR NEAR THE SRS COMPONENTS OR THE SRS
WIRING, REFER TO THE SRS SERVICE
INFORMATION. FAILURE TO FOLLOW WARNINGS
COULD RESULT IN POSSIBLE AIR BAG
DEPLOYMENT, PERSONAL INJURY, OR
OTHERWISE UNNEEDED SRS SYSTEM REPAIRS.
CAUTION: Always use the correct fastener in the
proper location. When you replace a fastener, use
ONLY the exact part number for that application.
ISUZU will call out those fasteners that require a
replacement after removal. ISUZU will also call out
the fasteners that require thread lockers or thread
sealant. UNLESS OTHERWISE SPECIFIED, do not
use supplemental coatings (Paints, greases, or other
corrosion inhibitors) on threaded fasteners or
fastener joint interfaces. Generally, such coatings
adversely affect the fastener torque and the joint
clamping force, and may damage the fastener. When
you install fasteners, use the correct tightening
sequence and specifications. Following these
instructions can help you avoid damage to parts and
systems.

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±18
Circuit Diagram
D04RW052

5A±1 BRAKE CONTROL SYSTEM
BRAKES
CONTENTS
Brake Control System 5A. . . . . . . . . . . . . . . . . . . .
Anti±lock Brake System 5B. . . . . . . . . . . . . . . . . . Power±Assisted Brake System 5C. . . . . . . . . . . .
Parking Brakes 5D. . . . . . . . . . . . . . . . . . . . . . . . .
BRAKE CONTROL SYSTEM
CONTENTS
Service Precaution 5A±2. . . . . . . . . . . . . . . . . . . . . .
General Description 5A±3. . . . . . . . . . . . . . . . . . . . .
System Components 5A±3. . . . . . . . . . . . . . . . . . .
Electronic Hydraulic Control Unit (EHCU) 5A±3.
ABS Warning Light 5A±4. . . . . . . . . . . . . . . . . . . .
Wheel Speed Sensor 5A±4. . . . . . . . . . . . . . . . . .
G-Sensor 5A±4. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Normal and Anti-lock Braking 5A±4. . . . . . . . . . .
Brake Pedal Travel 5A±4. . . . . . . . . . . . . . . . . . . .
Acronyms and Abbreviations 5A±4. . . . . . . . . . . .
General Diagnosis 5A±5. . . . . . . . . . . . . . . . . . . . . . .
General Information 5A±5. . . . . . . . . . . . . . . . . . . .
ABS Service Precautions 5A±5. . . . . . . . . . . . . . .
Computer System Service Precautions 5A±5. . .
General Service Precautions 5A±5. . . . . . . . . . . .
Note on Intermittents 5A±5. . . . . . . . . . . . . . . . . . .
Test Driving ABS Complaint Vehicles 5A±6. . . . .
ªABSº Warning Light 5A±6. . . . . . . . . . . . . . . . . . .
Normal Operation 5A±6. . . . . . . . . . . . . . . . . . . . .
Basic Diagnostic Flow Chart 5A±6. . . . . . . . . . . .
Basic Inspection Procedure 5A±7. . . . . . . . . . . . .
Tech 2 Scan Tool 5A±8. . . . . . . . . . . . . . . . . . . . . .
Getting Started 5A±9. . . . . . . . . . . . . . . . . . . . . . . .
Operating Procedure 5A±10. . . . . . . . . . . . . . . . . . .
Data List 5A±11. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
EHCU Connector Pin-out Checks 5A±12. . . . . . . .
Circuit Diagram (LHD model / 6VD1 and
4JG2) 5A±13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Circuit Diagram (LHD model / 4JG2) 5A±14. . . . .
Circuit Diagram (LHD model / 4JG2) 5A±15. . . . .
Circuit Diagram (LHD model / 6VD1) 5A±16. . . . .
Circuit Diagram (LHD model / 6VD1) 5A±17. . . . .
Connector List (LHD model) 5A±18. . . . . . . . . . . .
Part Location (LHD model) 5A±20. . . . . . . . . . . . . .
Circuit Diagram (RHD model / 6VD1 and
4JG2) 5A±21. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Circuit Diagram (RHD model / 4JG2) 5A±22. . . . .
Circuit Diagram (RHD model / 4JG2) 5A±23. . . . .
Circuit Diagram (RHD model / 6VD1) 5A±24. . . . .
Circuit Diagram (RHD model / 6VD1) 5A±25. . . . .
Circuit Diagram (RHD model / 6VE1 and
4JX1) 5A±26. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Circuit Diagram (RHD model / 4JX1) 5A±27. . . . .
Circuit Diagram (RHD model / 4JX1) 5A±28. . . . .
Circuit Diagram (RHD model / 6VE1) 5A±29. . . . .
Circuit Diagram (RHD model / 6VE1) 5A±30. . . . .
Connector List (RHD model) 5A±31. . . . . . . . . . . .
Part Location (RHD model) 5A±34. . . . . . . . . . . . .
Symptom Diagnosis 5A±35. . . . . . . . . . . . . . . . . . . . .
Chart A±1 ABS Works Frequently But
Vehicle Does Not Decelerate 5A±35. . . . . . . . . . .
Chart TA-1 ABS Works Frequently But
Vehicle Does Not Decelerate (Use
TECH 2) 5A±36. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chart A-2 Uneven Braking Occurs While
ABS Works 5A±36. . . . . . . . . . . . . . . . . . . . . . . . . . .
Chart A-3, TA-3 The Wheels Are Locked 5A±36.
Chart A-4 Brake Pedal Feed Is Abnormal 5A±37.
Chart A-5, TA-5 Braking Sound (From
EHCU) Is Heard While Not Braking 5A±38. . . . . .
Diagnostic Trouble Codes 5A±39. . . . . . . . . . . . . . . .
Diagnosis By ªABSº Warning Light
Illumination Pattern 5A±40. . . . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Codes (DTCs) 5A±40. . . . . . .
Chart B-1 With the key in the ON position
(Before starting the engine). Warning light
(W/L) is not activated. 5A±43. . . . . . . . . . . . . . . . .
Chart B-2 EHCU Abnormality (DTC 14) 5A±43. . .
Chart B-3 Power Voltage Drop (DTC 15) 5A±44. .
Chart B-4 CLASS-2 Communication Line
Abnormality (DTC 16) 5A±44. . . . . . . . . . . . . . . . .
Chart B-5 G-Sensor Circuit (DTC 21) 5A±45. . . . .
Chart B-6 Abnormal Transmission Input
(DTC 23) 5A±46. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chart B-7 Transfer Monitor (DTC 24) 5A±47. . . . .
Chart B-8 EHCU Pump Motor And Motor
Relay Circuit (DTC 32) 5A±47. . . . . . . . . . . . . . . . .
Chart B-9 EHCU Pump Valve And Valve
Relay Circuit (DTC 35) 5A±47. . . . . . . . . . . . . . . . .
Chart B-10 FL Isolation Solenoid Valve
Abnormality (DTC 41) 5A±48. . . . . . . . . . . . . . . . .
Chart B-11 FL Dump Solenoid Valve
Abnormality (DTC 42) 5A±48. . . . . . . . . . . . . . . . .
Chart B-12 FR Isolation Solenoid Valve
Abnormality (DTC 43) 5A±48. . . . . . . . . . . . . . . . .
Chart B-13 FR Dump Solenoid Valve
Abnormality (DTC 44) 5A±49. . . . . . . . . . . . . . . . .
Chart B-14 Rear Isolation Solenoid Valve
Abnormality (DTC 45) 5A±49. . . . . . . . . . . . . . . . .
Chart B-15 Rear Dump Solenoid Valve
Abnormality (DTC 46) 5A±49. . . . . . . . . . . . . . . . .

5A±13 BRAKE CONTROL SYSTEM
Circuit Diagram (LHD model / 6VD1 and 4JG2)
D08RW793

5A±14
BRAKE CONTROL SYSTEM
Circuit Diagram (LHD model / 4JG2)
D08RW792

5A±15 BRAKE CONTROL SYSTEM
Circuit Diagram (LHD model / 4JG2)
D08RW791