ISUZU AXIOM 2002 Service Repair Manual

5A±52BRAKE CONTROL SYSTEM
Chart B-24 Wheel Speed Input Abnormality (DTC 65 (Flash out) / C0238 (Serial
communications))
StepActionYe sNo
1Using TECH 2?Go to Step 2Go to Step 3
21. Connect TECH 2.
2. Select Snap shot manual trigger.
3. With wheel speed data displayed, run the vehicle when speed
has arrived at 30 km/h (18 mph).
4. Check speed data on each wheel (refer to the criterion given
below). * 1
Is the abnormal sensor condition found?
Replace.
Go to
Step 8
Go to Step 3
All the sensors
should follow the
following
flowchart (without
using TECH 2).
3Is there play in sensor/sensor ring?Repair.
Go to
Step 8Go to Step 4
4Is there powdered iron sticking to sensor/sensor ring?Repair.
Go to
Step 8Go to Step 5
5Is there a broken tooth or indentation in sensor ring?Replace sensor
ring.
Go to
Step 8Go to Step 6
6Is there play in wheel bearing?Adjust or repair.
Go to
Step 8Go to Step 7
7Is the check wiring between sensor and coil integrated module
normal?
Replace EHCU.
Go to
Step 8
Repair, and
perform system
self-check.
Go to
Step 8
81. Reconnect all components, ensure all components are
properly mounted.
2. Clear diagnostic trouble code.
Was this step finished?
Repeat `Basic
diagnostic flow
chartº
Go to Step 8
Sensor Signal Abnormality Criteria using TECH 2
1. While driving, the speed of one or two wheels is 25%
or more higher or lower than that of the other wheels.
2. The speed of one or two wheels is 10 km/h (6 mph) or
more higher or lower than that of the other wheels.
3. During steady driving, wheel speed changes abruptly.
*1 The vehicle must run on a level paved road.
NOTE: Even after repairing the faulty part the warning
light (W/L) does not go out if the vehicle is at a stop.
Turn the ignition switch to the ON position and drive the
vehicle at 12 km/h (8 mph) or higher to make sure that the
warning light goes out.
It is important to verify that the correct tires are installed
on vehicle.

5A±53
BRAKE CONTROL SYSTEM
Unit Inspection Procedure
This section describes the following inspection
procedures referred to during
Symptom Diagnosis and
Diagnosis By ªABSº Warning Light Illumination Pattern
without TECH 2with TECH 2
Sensor Output InspectionChart C-1-1 to C-1-3Chart TC-1
Chart C-1-1 FL Sensor Output Inspection Procedure
StepActionYe sNo
11. Turn the key off.
2. Disconnect coil integrated module connector.
3. Jack up the vehicle with all four wheels off the ground.
Measure the AC voltage between coil integrated module
connector terminals while turning FL wheel at a speed of 1
RPS:
Is the voltage between coil integrated module connector (C-6)
terminals 2 and 10 less than 200 mV?
Go to Step 2
OK.
Go to
Step 3
21. Disconnect the wheel speed sensor.
2. Measure resistance between the wheel speed sensor
connector terminals 1 and 2.
Is the check between connector (C-28) terminals 1 and 2 within
2.0k - 2.8k ohms?Connector is
faulty, or open or
short circuit of
harness between
wheel speed
sensor connector
and coil
integrated
module.
Inspect and
correct the
connector or
harness.
Go to
Step 3
Wheel speed
sensor is faulty.
Replace the
wheel speed
sensor.
Go to
Step 3
3Reconnect all components, ensure all components are properly
mounted.
Was this step finished?Repeat the ªBasic
diagnostic flow
chartº
Go to Step 3

5A±54BRAKE CONTROL SYSTEM
Chart C-1-2 FR Sensor Output Inspection Procedure
StepActionYe sNo
11. Turn the key off.
2. Disconnect coil integrated module connector.
3. Jack up the vehicle with all four wheels off the ground.
Measure the AC voltage between coil integrated module
connector terminals while turning FR wheel at a speed of 1
RPS:
Is the voltage between coil integrated module connector (C-6)
terminals 3 and 11 less than 200 mV?
Go to Step 2
OK.
Go to
Step 3
21. Disconnect the wheel speed sensor.
2. Measure resistance between the wheel speed sensor
connector terminals 1 and 2.
Is the check between connector (C-1) terminals 1 and 2 within
2.0k - 2.8k ohms?Connector is
faulty, or open or
short circuit of
harness between
wheel speed
sensor connector
and coil
integrated
module.
Inspect and
correct the
connector or
harness.
Go to
Step 3
Wheel speed
sensor is faulty.
Replace the
wheel speed
sensor.
Go to
Step 3
3Reconnect all components, ensure all components are properly
mounted.
Was this step finished?Repeat the ªBasic
diagnostic flow
chartº
Go to Step 3
Chart C-1-3 Rear Sensor Output Inspection Procedure
StepActionYe sNo
11. Turn the key off.
2. Disconnect coil integrated module connector.
3. Jack up the vehicle with all four wheels off the ground measure
the AC voltage between coil integrated module connector
terminals while turning Rear wheel at a speed of 1 RPS:
Is the check between coil integrated module connector (C-6)
terminals 4 and 12 than under 200 mV?
Go to Step 2
OK.
Go to
Step 3
21. Disconnect the wheel speed sensor.
2. Measure resistance between the wheel speed sensor
connector terminals 1 and 2.
Is the check between connector (F-4) terminals 1 and 2 within
1.0k - 1.7k ohms?Connector is
faulty, or open or
short circuit of
harness between
wheel speed
sensor connector
and coil
integrated
module.
Inspect and
correct the
connector or
harness.
Go to
Step 3
Wheel speed
sensor is faulty.
Replace the
wheel speed
sensor.
Go to
Step 3
3Reconnect all components, ensure all components are properly
mounted.
Was this step finished?Repeat the ªBasic
diagnostic flow
chartº
Go to Step 3

5A±55
BRAKE CONTROL SYSTEM
Chart TC-1 Sensor Output Inspection Procedure
StepActionYe sNo
11. Connect TECH 2.
2. Check the wheel speed of each sensor by Data List.
Is the vehicle speed normal?
Go to Step 6Go to Step 2
2Check the sensor harness for suspected disconnection (check
while shaking harness/connector).
Is the sensor harness connection normal?Replace speed
sensor.
Go to
Step 4
Repair.
Go to
Step 3
3Check the wheel speed of each sensor by Data List.
Is the vehicle speed normal?
Go to Step 6Go to Step 4
4Check the sensor rotor.
Is the sensor rotor normal?Replace speed
sensor.
Go to
Step 5
Replace sensor
rotor.
Go to
Step 5
5Check the harness between coil integrated module and speed
sensor.
Is the harness connection normal?
Go to Step 6
Repair harness or
connector
between coil
integrated
module and
speed sensor.
Go to
Step 6
6Reconnect all components, ensure all components are properly
mounted.
Was this step finished?Repeat the ªBasic
diagnostic flow
chartº
Go to Step 6

5A±56BRAKE CONTROL SYSTEM
Special Tools
ILLUSTRATIONTOOL NO.
TOOL NAME
J±35616
Connector test adapter
kit
J±39200
High impedance
multimeter
7000086±ISU
Tech 2 Set
(1) PCMCIA Card
(2) SAE 16/19 Adapter
(3) DLC Cable
(4) Tech 2

5B±1 ANTI±LOCK BRAKE SYSTEM
AXIOM
BRAKES
ANTI-LOCK BRAKE SYSTEM
CONTENTS
Service Precaution 5B±1. . . . . . . . . . . . . . . . . . . . . .
Electronic Hydraulic Control Unit 5B±2. . . . . . . . . .
Electronic Hydraulic Control Unit and
Associated Parts 5B±2. . . . . . . . . . . . . . . . . . . . . .
Removal 5B±2. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disassembled View 5B±3. . . . . . . . . . . . . . . . . . . .
Disassembly 5B±3. . . . . . . . . . . . . . . . . . . . . . . . . .
Reassembly 5B±3. . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 5B±3. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Front Wheel Speed Sensor 5B±4. . . . . . . . . . . . . . . Front Wheel Speed Sensor and Associated
Parts 5B±4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 5B±4. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 5B±4. . . . . . . . . . . . . . . . . .
Installation 5B±4. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Rear Wheel Speed Sensor 5B±5. . . . . . . . . . . . . . .
Removal 5B±5. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 5B±5. . . . . . . . . . . . . . . . . .
Installation 5B±5. . . . . . . . . . . . . . . . . . . . . . . . . . . .
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.

5B±2ANTI±LOCK BRAKE SYSTEM
Electronic Hydraulic Control Unit
Electronic Hydraulic Control Unit and Associated Parts
350R100003
Legend
(1) EHCU
(2) Bolt(3) Bracket
(4) Bolt and Nut
Removal
1. Remove brake pipes.

After disconnecting brake pipe, cap or tape the
openings of the brake pipe to prevent the entry of
foreign matter.
2. Remove three bracket fixing bolts.
3. Disconnect red clip from harness connector.
350RW018

5B±3 ANTI±LOCK BRAKE SYSTEM
4. Remove harness connector.
5. Remove EHCU ASM.
6. Remove EHCU.
Disassembled View
350RW025
Legend
(1) Fixing Bolts
(2) Coil Integrated Module
(3) Hydraulic Unit (H/U)
Disassembly
1. Remove fixing bolts from EHCU.
2. Remove coil integrated module from hydraulic unit.
Reassembly
To reassembly, follow the disassembly steps in the
reverse order, noting the following points:
Torque
Fixing bolts: 4.4 N´m (39 lb in)
Installation
To install, follow the removal steps in the reverse order,
noting the following points:
Torque
Hydraulic unit fixing nuts : 22 N´m (16 lb ft)
Ground cable : 14 N´m (10 lb ft)
Brake pipe (joint bolts) : 16 N´m (12 lb ft)

After installing the hydraulic unit, bleed brakes
completely. See
Section 5A ªHydraulic Brakesº.

5B±4ANTI±LOCK BRAKE SYSTEM
Front Wheel Speed Sensor
Front Wheel Speed Sensor and Associated Parts
350RS033
Legend
(1) Speed Sensor Connector
(2) Sensor Cable Fixing Bolt (Upper side)(3) Sensor Cable Fixing Bolt (Lower side)
(4) Sensor Cable Fixing Bolt (Sensor side)
(5) Speed Sensor
Removal
1. Remove speed sensor connector.
2. Remove sensor cable fixing bolt (Upper side).
3. Remove sensor cable fixing bolt (Lower side).
4. Remove the speed sensor cable fixing bolt.
5. Remove speed sensor.
Inspection and Repair
1. Check the speed sensor pole piece for presence of
foreign materials; remove any dirt, etc.
2. Check the pole piece for damage; replace speed
sensor if necessary.
3. Check the speed sensor cable for short or open
circuit, and replace with a new one if necessary.
To check for cable short or open, bend or stretch the
cable while checking for continuity.
4. Check the sensor ring for damage including tooth
chipping, and if damaged, replace the sensor ring
assembly. Refer to removal of the sensor ring in
Section
4C ªFront hub and discº.
Installation
1. Install speed sensor and take care not to hit the speed
sensor pole piece during installation.
2. Install speed sensor fixing bolt and tighten the fixing
bolt to the specified torque.
Torque: 11 N´m (95 lb in)
3. Install speed sensor cable fixing bolt (Lower side) and
tighten the fixing bolt to the specified torque.
Torque : 24 N´m (17 lb ft)
4. Install speed sensor cable fixing bolt (Upper side) and
tighten the fixing bolt to the specified torque.
Torque : 6 N´m (52 lb in)
NOTE: Confirm that a white line marked on the cable is
not twisted when connecting the speed sensor cable.
5. Install speed sensor connector.

5B±5 ANTI±LOCK BRAKE SYSTEM
Rear Wheel Speed Sensor
Removal
1. Disconnect harness connector (1).
2. Remove sensor fixing bolt (2) .
3. Remove speed sensor (3).
350R100004
Inspection and Repair
1. Check speed sensor pole piece for presence of
foreign materials; remove any dirt, etc.
2. Check the pole piece for damage, and replace speed
sensor if necessary.
3. Check speed sensor cable for short or open, and
replace with a new one if necessary. To check for
cable short or open, bend or stretch the cable while
checking for continuity.
4. Check the sensor ring for damage including tooth
chipping, and if damaged, replace the axle shaft
assembly. Refer to removal of the sensor ring in
Section
4A2 ªDifferential (Rear)º.
Installation
1. Install speed sensor (3).
2. Tighten the sensor fixing bolt (2) to the specified
torque.
Torque : 24 N´m (17 lb ft)
3. Connect harness connector (1).
350R100004