service OPEL FRONTERA 1998 Workshop Manual

DRIVE LINE CONTROL SYSTEM (TOD) 4B2–40
Tech 2 Scan Tool
From 98 MY, Isuzu dealer service departments are
recommended to use Tech 2. Please refer to Tech 2 scan
tool user guide.
901RW180
Legend
(1) PCMCIA Card
(2) RS 232 Loop Back Connector(3) SAE 16/19 Adaptor
(4) DLC Cable
(5) Tech–2

DRIVE LINE CONTROL SYSTEM (TOD) 4B2–116
StepActionYe sNo
1Are the front and rear tires in specified size?
Go to Step 2
Replace the tires
with specified
ones, and service
the new tires.
Go to Step 16
2Is the tire pressure correct?
Go to Step 3
In flate tries to
recommended
pressure.
Go to Step 16
3Are the tires free from abnormal wear?
Go to Step 4
Replace the tires
with specified
ones, and service
the new tires.
Go to Step 16
4Are different types of tires used?
Go to Step 5
Replace the tires
with specified
ones, and service
the new tires.
Go to Step 16
51. Start the engine.
2. Shift the transfer lever to the high position and switch the 4WD
AUTO SW to 4WD position.
3. Fully turn the steering to the left (or right) end, and select the D
range and start the creep run.
Does the tight corner braking occur? Is the judder with chug-chug
sound observed? * Use caution on the operation.
Go to Step 6 Go to Step 11
61. Shift the transfer lever to the high position and switch the 4WD
AUTO SW to the 2H position.
2. Fully turn the steering to the left (or right) end, and select the D
range and start the creep run.
Does the tight corner braking occur? Is the judder with chug-chug
sound observed? * Use caution on the operation.
Go to Step 7 Go to Step 14
7Is an LSD mounted to the rear differential? Go to Step 8 Go to Step 9
8Is the genuine LSD oil used in the rear differential?
Go to Step 9
Replace the
differential oil.
Go to Step 16
9Does the engine output the power correctly?
Go to Step 10
Check the
engine.
Go to Step 16
10Do the speed sensors work correctly? (Check trouble codes.)The ECU has
failed. Replace
the ECU.
Go to Step 16
Replace the
speed sensors.
Go to Step 16
11Is the tight corner braking observed only when the brake is
applied?
Go to Step 12
Conduct full
steering under
WOT.
Go to Step 5
121. Turn on the starter switch.
Is the battery voltage observed between terminals 11 and 19?
Go to Step 13
Repair the circuit
of terminal 11
(ABS IN).
Go to Step 16

4C–1 DRIVE SHAFT SYSTEM
DRIVELINE/AXLE
DRIVE SHAFT SYSTEM
CONTENTS
Service Precaution 4C–2. . . . . . . . . . . . . . . . . . . . . .
General Description 4C–2. . . . . . . . . . . . . . . . . . . . .
Diagnosis 4C–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Rear Axle Shaft 4C–4. . . . . . . . . . . . . . . . . . . . . . . . .
Rear Axle Shaft and Associated Parts 4C–4. . . .
Removal 4C–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 4C–5. . . . . . . . . . . . . . . . . .
Oil Seal Replacement 4C–6. . . . . . . . . . . . . . . . . .
Installation 4C–6. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Special Tools 4C–8. . . . . . . . . . . . . . . . . . . . . . . . . . .
Front Hub and Disc (with Shift on the Fly) 4C–9. .
Disassembled View 4C–9. . . . . . . . . . . . . . . . . . . .
Disassembly 4C–9. . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 4C–10. . . . . . . . . . . . . . . . . .
Reassembly 4C–11. . . . . . . . . . . . . . . . . . . . . . . . . .
Front Hub and Disc with Manual Locking Hub 4C–14
Disassembled View 4C–14. . . . . . . . . . . . . . . . . . . .
Disassembly 4C–14. . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 4C–16. . . . . . . . . . . . . . . . . .
Reassembly 4C–16. . . . . . . . . . . . . . . . . . . . . . . . . .
Main Data and Specifications 4C–20. . . . . . . . . . . . .
Special Tools 4C–21. . . . . . . . . . . . . . . . . . . . . . . . . . .
Front Drive Shaft Joint 4C–22. . . . . . . . . . . . . . . . . . .
Front Drive Shaft Joints Replacement 4C–22. . . .
Front Axle Drive Shaft 4C–23. . . . . . . . . . . . . . . . . . .
Front Axle Drive Shaft and Associated
Parts 4C–23. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disassembly 4C–24. . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 4C–25. . . . . . . . . . . . . . . . . .
Bushing Replacement 4C–25. . . . . . . . . . . . . . . . . . Reassembly 4C–26. . . . . . . . . . . . . . . . . . . . . . . . . .
Shift On The Fly System 4C–28. . . . . . . . . . . . . . . . .
Shift On The Fly System and Associated
Parts 4C–28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disassembly 4C–28. . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 4C–30. . . . . . . . . . . . . . . . . .
Main Data and Specifications 4C–35. . . . . . . . . . .
Special Tools 4C–36. . . . . . . . . . . . . . . . . . . . . . . . . .
Front Propeller Shaft 4C–37. . . . . . . . . . . . . . . . . . . . .
General Description 4C–37. . . . . . . . . . . . . . . . . . . . .
Front Propeller Shaft and Associated Parts 4C–38
Removal 4C–38. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 4C–39. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disassembly (Except TOD 4
4) 4C–40. . . . . . . . .
Universal Joint Disassembly 4C–41. . . . . . . . . . . .
Inspection and Repair 4C–42. . . . . . . . . . . . . . . . . .
Universal Joint Reassembly 4C–45. . . . . . . . . . . . .
Reassembly (Except TOD 4
4) 4C–46. . . . . . . . . .
Main Data and Specifications 4C–47. . . . . . . . . . .
Rear Propeller Shaft 4C–48. . . . . . . . . . . . . . . . . . . . .
General Description 4C–48. . . . . . . . . . . . . . . . . . . . .
Rear Propeller Shaft and Associated Parts 4C–48
Removal 4C–49. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 4C–49. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disassembly 4C–50. . . . . . . . . . . . . . . . . . . . . . . . . .
Universal Joint Disassembly 4C–51. . . . . . . . . . . .
Inspection and Repair 4C–52. . . . . . . . . . . . . . . . . .
Universal Joint Reassembly 4C–53. . . . . . . . . . . . .
Reassembly 4C–54. . . . . . . . . . . . . . . . . . . . . . . . . .
Main Data and Specifications 4C–55. . . . . . . . . . .

4C–2
DRIVE SHAFT SYSTEM
Service Precaution
WARNING: IF SO EQUIPPED 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.
General Description
This publication contains essential removal, installation,
adjustment and maintenance procedures.
The front axle utilizes a central disconnect type front
axle/transfer case system.
The drive axles are completely flexible assemblies,
consisting of inner and outer constant velocity (CV) drive
shaft joints connected by an axle shaft.
For description of propeller shaft and universal joint, refer
to Front/Rear Propeller Shaft in this section.

TRANSFER CASE (STANDARD TYPE)
4D1–1
DRIVELINE/AXLE
TRANSFER CASE (STANDARD TYPE)
CONTENTS
Service Precaution 4D1–1. . . . . . . . . . . . . . . . . . . . . .
General Description 4D1–2. . . . . . . . . . . . . . . . . . . . .
Transfer Rear Oil Seal 4D1–8. . . . . . . . . . . . . . . . . . .
Removal 4D1–8. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 4D1–8. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Transfer Case Assembly 4D1–9. . . . . . . . . . . . . . . . .
Removal 4D1–9. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 4D1–10. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Transfer Rear Cover Assembly
(4WD Switch Model) 4D1–11. . . . . . . . . . . . . . . . . . . .
Transfer Rear Cover Assembly and
Associated Parts 4D1–11. . . . . . . . . . . . . . . . . . . . . .
Removal 4D1–12. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 4D1–13. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disassembly 4D1–16. . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 4D1–17. . . . . . . . . . . . . . . . . .
Reassembly 4D1–17. . . . . . . . . . . . . . . . . . . . . . . . . .
Transfer Rear Cover Assembly
(Except 4WD Switch Model) 4D1–19. . . . . . . . . . . . . . Transfer Rear Cover Assembly and
Associated Parts 4D1–19. . . . . . . . . . . . . . . . . . . . . .
Removal 4D1–20. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 4D1–20. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disassembly 4D1–23. . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 4D1–24. . . . . . . . . . . . . . . . . .
Reassembly 4D1–24. . . . . . . . . . . . . . . . . . . . . . . . . .
Detent, Shift Arm, and Interlock Pin 4D1–26. . . . . . . .
Disassembled View 4D1–26. . . . . . . . . . . . . . . . . . . .
Disassembly 4D1–26. . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 4D1–28. . . . . . . . . . . . . . . . . .
Reassembly 4D1–28. . . . . . . . . . . . . . . . . . . . . . . . . .
Transfer Case Assembly 4D1–30. . . . . . . . . . . . . . . . .
Disassembled View 4D1–30. . . . . . . . . . . . . . . . . . . .
Disassembly 4D1–31. . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 4D1–33. . . . . . . . . . . . . . . . . .
Reassembly 4D1–37. . . . . . . . . . . . . . . . . . . . . . . . . .
Main Data and Specifications 4D1–43. . . . . . . . . . . . .
Special Tools 4D1–46. . . . . . . . . . . . . . . . . . . . . . . . . . .
Service Precaution
WARNING: THIS VEHICLE HAS 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.

4D2–1 TRANSFER CASE (TOD)
DRIVELINE/AXLE
TRANSFER CASE (TOD)
CONTENTS
Service Precaution 4D2–1. . . . . . . . . . . . . . . . . . . . . .
Transfer Case Assembly 4D2–2. . . . . . . . . . . . . . . . .
Removal 4D2–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 4D2–3. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Transfer Rear Oil Seal 4D2–5. . . . . . . . . . . . . . . . . . .
Transfer Rear Oil Seal and Associated
Parts 4D2–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 4D2–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 4D2–5. . . . . . . . . . . . . . . . . . . . . . . . . . . .
TOD ECU 4D2–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 4D2–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 4D2–7. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Unit Repair 4D2–8. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection 4D2–8. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Transfer Case 4D2–9. . . . . . . . . . . . . . . . . . . . . . . . . .
Disassembled View 4D2–9. . . . . . . . . . . . . . . . . . . .
Disassembly 4D2–9. . . . . . . . . . . . . . . . . . . . . . . . . .
Reassembly 4D2–10. . . . . . . . . . . . . . . . . . . . . . . . . .
Transfer Cover Assembly 4D2–12. . . . . . . . . . . . . . . .
Disassembled View 4D2–12. . . . . . . . . . . . . . . . . . . .
Disassembly 4D2–12. . . . . . . . . . . . . . . . . . . . . . . . . .
Reassembly 4D2–14. . . . . . . . . . . . . . . . . . . . . . . . . .
Transfer Case Assembly Clutch Pack and
Clutch Cam 4D2–16. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disassembled View 4D2–16. . . . . . . . . . . . . . . . . . . . Disassembly 4D2–16. . . . . . . . . . . . . . . . . . . . . . . . . .
Sprocket and Mechanical Lock 4D2–18. . . . . . . . . . . .
Disassembled View 4D2–18. . . . . . . . . . . . . . . . . . . .
Disassembly 4D2–18. . . . . . . . . . . . . . . . . . . . . . . . . .
Output Shafts and Shift Control Shaft 4D2–20. . . . . .
Disassembled View 4D2–20. . . . . . . . . . . . . . . . . . . .
Disassembly 4D2–21. . . . . . . . . . . . . . . . . . . . . . . . . .
Transfer Case 4D2–23. . . . . . . . . . . . . . . . . . . . . . . . . .
Disassembled View 4D2–23. . . . . . . . . . . . . . . . . . . .
Disassembly 4D2–24. . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 4D2–26. . . . . . . . . . . . . . . . . .
Transfer Case 4D2–30. . . . . . . . . . . . . . . . . . . . . . . . . .
Disassembled View 4D2–30. . . . . . . . . . . . . . . . . . . .
Reassembly 4D2–30. . . . . . . . . . . . . . . . . . . . . . . . . .
Output Shafts and Shift Control Shaft 4D2–34. . . . . .
Disassembled View 4D2–34. . . . . . . . . . . . . . . . . . . .
Reassembly 4D2–34. . . . . . . . . . . . . . . . . . . . . . . . . .
Sprocket and Mechanical Lock 4D2–37. . . . . . . . . . . .
Disassembled View 4D2–37. . . . . . . . . . . . . . . . . . . .
Reassembly 4D2–37. . . . . . . . . . . . . . . . . . . . . . . . . .
Clutch Pack and Clutch Cam 4D2–39. . . . . . . . . . . . .
Disassembled View 4D2–39. . . . . . . . . . . . . . . . . . . .
Reassembly 4D2–39. . . . . . . . . . . . . . . . . . . . . . . . . .
Main Data and Specifications 4D2–41. . . . . . . . . . . . .
Special Tools 4D2–43. . . . . . . . . . . . . . . . . . . . . . . . . . .
Service Precaution
WARNING: IF SO EQUIPPED 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.

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. . . . .
“ABS” 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 “ABS” 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–2
BRAKE CONTROL SYSTEM
Chart B-16 FL Speed Sensor Disconnection
(DTC 51) 5A–50. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chart B-17 FR Speed Sensor Disconnection
(DTC 52) 5A–50. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chart B-18 RL Speed Sensor Disconnection
(DTC 53) 5A–51. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chart B-19 RR Speed Sensor Disconnection
(DTC 54) 5A–51. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chart B-20 FL Speed Sensor Short Circuit
(DTC 61) 5A–52. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chart B-21 FR Speed Sensor Short Circuit
(DTC 62) 5A–53. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chart B-22 RL Speed Sensor Short Circuit
(DTC 63) 5A–54. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chart B-23 RR Speed Sensor Short Circuit
(DTC 64) 5A–55. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chart B-24 Sensor Signal Input Abnormality
(DTC 65) 5A–56. . . . . . . . . . . . . . . . . . . . . . . . . . . . Sensor Signal Abnormality Criteria using
TECH 2 5A–56. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Unit Inspection Procedure 5A–57. . . . . . . . . . . . . . . .
Chart C-1-1 FL Sensor Output Inspection
Procedure 5A–57. . . . . . . . . . . . . . . . . . . . . . . . . . .
Chart C-1-2 FR Sensor Output Inspection
Procedure 5A–58. . . . . . . . . . . . . . . . . . . . . . . . . . .
Chart C-1-3 RL Sensor Output Inspection
Procedure 5A–58. . . . . . . . . . . . . . . . . . . . . . . . . . .
Chart C-1-4 RR Sensor Output Inspection
Procedure 5A–59. . . . . . . . . . . . . . . . . . . . . . . . . . .
Chart TC-1 Sensor Output Inspection
Procedure (Use TECH 2) 5A–59. . . . . . . . . . . . . .
Chart C-2 Transmission Input Inspection
Procedure 5A–60. . . . . . . . . . . . . . . . . . . . . . . . . . .
Chart TC-2 Transmission Input Inspection
Procedure (Use TECH 2) 5A–61. . . . . . . . . . . . . .
Special Tools 5A–62. . . . . . . . . . . . . . . . . . . . . . . . . . .
Service Precaution
WARNING: IF SO EQUIPPED 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.

5A–5 BRAKE CONTROL SYSTEM
FR
Front Right
GEN
Generator
MV
Millivolts
RL
Rear Left
RR
Rear RightRPS
Revolution per Second
VDC
Vo l t s D C
VA C
Vo l t s A C
W/L
Warning Light
WSS
Wheel Speed Sensor
General Diagnosis
General Information
ABS malfunction can be classified into two types, those
which can be detected by the ABS warning light and those
which can be detected as a vehicle abnormality by the
driver.
In either case, locate the fault in accordance with the
“BASIC DIAGNOSTIC FLOWCHART” and repair.
Please refer to Section 5C for the diagnosis of
mechanical troubles such as brake noise, brake judder
(brake pedal or vehicle vibration felt when braking),
uneven braking, and parking brake trouble.
ABS Service Precautions
Required Tools and Items:
Box Wrench
Brake Fluid
Special Tool
Some diagnosis procedures in this section require the
installation of a special tool.
J-39200 High Impedance Multimeter
When circuit measurements are requested, use a circuit
tester with high impedance.
Computer System Service Precautions
The Anti-lock Brake System interfaces directly with the
Electronic Hydraulic Control Unit (EHCU) which is a
control computer that is similar in some regards to the
Powertrain Control Module. These modules are designed
to withstand normal current draws associated with
vehicle operation. However, care must be taken to avoid
overloading any of the EHCU circuits. In testing for opens
or shorts, do not ground or apply voltage to any of the
circuits unless instructed to do so by the appropriate
diagnostic procedure. These circuits should only be
tested with a high impedance multimeter (J-39200) or
special tools as described in this section. Power should
never be removed or applied to any control module with
the ignition in the “ON” position.
Before removing or connecting battery cables, fuses or
connectors, always turn the ignition switch to the “OFF”
position.
General Service Precautions
The following are general precautions which should be
observed when servicing and diagnosing the Anti-lock
Brake System and/or other vehicle systems. Failure toobserve these precautions may result in Anti-lock Brake
System damage.
If welding work is to be performed on the vehicle using
an electric arc welder, the EHCU and valve block
connectors should be disconnected before the
welding operation begins.
The EHCU and valve block connectors should never
be connected or disconnected with the ignition “ON” .
EHCU of the Anti-lock Brake System are not
separately serviceable and must be replaced as
assemblies. Do not disassemble any component
which is designated as non-serviceable in this
Section.
If only rear wheels are rotated using jacks or drum
tester, the system will diagnose a speed sensor
malfunction and the “ABS” warning light will
illuminate. But actually no trouble exists. After
inspection stop the engine once and re-start it, then
make sure that the “ABS” warning light does not
illuminate.
If the battery has been discharged
The engine may stall if the battery has been completely
discharged and the engine is started via jumper cables.
This is because the Anti-lock Brake System (ABS)
requires a large quantity of electricity. In this case, wait
until the battery is recharged, or set the ABS to a
non-operative state by removing the fuse for the ABS
(40A). After the battery has been recharged, stop the
engine and install the ABS fuse. Start the engine again,
and confirm that the ABS warning light does not light.
Note on Intermittents
As with virtually any electronic system, it is difficult to
identify an intermittent failure. In such a case duplicating
the system malfunction during a test drive or a good
description of vehicle behavior from the customer may be
helpful in locating a “most likely” failed component or
circuit. The symptom diagnosis chart may also be useful
in isolating the failure. Most intermittent problems are
caused by faulty electrical connections or wiring. When
an intermittent failure is encountered, check suspect
circuits for:
Suspected harness damage.
Poor mating of connector halves or terminals not fully
seated in the connector body (backed out).
Improperly formed or damaged terminals.

5A–8
BRAKE CONTROL SYSTEM
Tech 2 Scan Tool
From 98 MY, Isuzu dealer service departments are
recommended to use Tech 2. Please refer to Tech 2 scan
tool user guide.
901RW257
Legend
(1) PCMCIA Card
(2) SAE 16/19 Adaptor(3) DLC Cable
(4) Tech–2