wheel OPEL FRONTERA 1998 Repair Manual

5A–39 BRAKE CONTROL SYSTEM
Diagnostic Trouble Codes
Choose and trace an appropriate flowchart by the
numbers listed below to find fault and repair.
Code
ItemDiagnosisChart No.
12Start CodeNormal—
14EHCU FunctionAbnormality in input/output, operational and
control circuitsB-2
15Power Voltage DropB-3
16CLASS–2 Communication Line Ab-
normalityB-4
21G-sensorWiring disconnectionB-5
23Transmission InputInput abnormalityB-6
24Transfer MonitorB-7
32Motor & Motor RelayShorted or disconnected coilB-8
35Valve RelayShorted or disconnected coil/wiringB-9
41FL Holding Solenoid ValveShorted or disconnected coil/wiringB-10
42FL Decompression Solenoid ValveShorted or disconnected coil/wiringB-11
43FR Holding Solenoid ValveShorted or disconnected coil/wiringB-12
44FR Decompression Solenoid ValveShorted or disconnected coil/wiringB-13
45Rear Holding Solenoid ValveShorted or disconnected coil/wiringB-14
46Rear Decompression Solenoid ValveShorted or disconnected coil/wiringB-15
51FL Wheel Speed SensorDisconnected coil/wiringB-16
52FR Wheel Speed SensorDisconnected coil/wiringB-17
53RL Wheel Speed SensorDisconnected coil/wiringB-18
54RR Wheel Speed SensorDisconnected coil/wiringB-19
61FL Wheel Speed SensorShorted coil/wiringB-20
62FR Wheel Speed SensorShorted coil/wiringB-21
63RL Wheel Speed SensorShorted coil/wiringB-22
64RR Wheel Speed SensorShorted coil/wiringB-23
65Sensor Signal InputWrong number of teethB-24

5A–40
BRAKE CONTROL SYSTEM
Diagnosis By “ABS” Warning Light
Illumination Pattern
In the event that there is abnormality in the “ABS” warning
light illumination pattern while the key is in the ON position
or if the warning light is actuated during driving, trouble
should be diagnosed on a illumination pattern basis as
follows:
No.
Condition“ABS” Warning Light Illumination PatternDiagnostic
1Warning light is actu-
ated normallyNormal
2Warning light is not litWarning light lighting circuit
trouble
Go to Chart B-1
3Warning light remains
ONDiagnostic trouble codes are
stored.
Display diagnostic trouble
codes and diagnose on a
code basis according to the
flow charts.
4Warning light is actu-
ated while drivingDiagnostic trouble codes are
stored.
Display diagnostic trouble
codes and diagnose on a
code basis according to the
flow charts.
Diagnostic Trouble Codes (DTCs)
When the warning light in the meter remains ON, the
EHCU stores the fault identification and disables the
ABS.
1. How to display and erase DTCs:
NOTE:
If DTCs are not displayed, harness C-4 connector
terminal 30 and I-10 connector terminal 2 may be
disconnected. Repair the harness and try DTC
display again.
DTCs can be displayed also by TECH 2. Select mode
“F0: Diagnostic Trouble Codes” from Application
Menu.
1. How to start DTC display:
Confirm that the vehicle has come to a complete
stop (with the wheels standing still) and that the
brake pedal is not depressed. (Unless these two
conditions are satisfied, DTC display cannot be
started.)
With IGN OFF, connect #12 terminal with #4
terminal or # 5 terminal (GND) . Then turn IGN ON.

5A–42
BRAKE CONTROL SYSTEM
4. Notes
If the following should occurs during Diagnostic
Trouble Code (DTC) display the display will be
discontinued. After initial check, the status that is
under the control of ABS will be returned :
– The vehicle starts (The wheels turn) or the brake
pedal is depressed.
Up to 3 different codes can be stored.
If the ABS should turn OFF due to an intermittent
defect, the system will be restored at the next key
cycle, if the initial check finds no abnormality (when
IGN is switched from OFF to ON).
5. An example of DTC display
Display of DTC 23
B05RW006
After displaying DTC 12 three times, one DTC after
another is displayed, starting with the most recent
one. (However, display is discontinued after about 5
minutes.)
B05RS005
The DTC 12 is displayed repeatedly. (display is
discontinued after about 5 minutes)

5A–56
BRAKE CONTROL SYSTEM
Chart B-24 Sensor Signal Input Abnormality (DTC 65)
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 8
Go to Step 4
4Is there powdered iron sticking to sensor/sensor ring?Repair.
Go to Step 8
Go to Step 5
5Is there a broken tooth or indentation in sensor ring?Replace sensor
ring.
Go to Step 8
Go to Step 6
6Is there play in wheel bearing?Adjust or repair.
Go to Step 8
Go to Step 7
7Is the check wiring between sensor and EHCU 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
chart.”
Go to Step 8
Sensor Signal Abnormality Criteria using
TECH 2
1. While driving, the speed of one or two wheels 25% or
more higher than that of the other wheels.
2. The speed of one or two wheels is 10 km/h (6 mph) or
more higher 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 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–57 BRAKE CONTROL SYSTEM
Unit Inspection Procedure
This section describes the following inspection
procedures referred to during “SYMPTOM DIAGNOSIS”
and “DIAGNOSIS BY ‘ABS’ WARNING LIGHT
ILLUMINATION PATTERN” :
without TECH 2with TECH 2
Wheel Speed Sensor Output InspectionChart C-1-1 to C-1-4Chart TC-1
Transmission SW InspectionChart C-2Chart TC-2
Chart C-1-1 FL Sensor Output Inspection Procedure
StepActionYe sNo
11. Turn the key off.
2. Disconnect EHCU connector.
3. Jack up the vehicle, With all four wheels off the ground.
Measure the AC voltage between EHCU connector terminals
while turning FL wheel at a speed of 1 RPS:
Is voltage between EHCU connector terminals 20 and 21 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 resistance between connector (C-13) terminals 1 and 2 within
1.3k - 1.9k ohms?Connector is
faulty, or open or
short circuit in
harness between
wheel speed
sensor connector
and EHCU.
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 and ensure all components are
properly mounted.
Was this step finished?Repeat the “Basic
diagnostic flow
chart.”
Go to Step 3

5A–58
BRAKE CONTROL SYSTEM
Chart C-1-2 FR Sensor Output Inspection Procedure
StepActionYe sNo
11. Turn the key off.
2. Disconnect EHCU connector.
3. Jack up the vehicle with all four wheels off the ground.
Measure the AC voltage between EHCU connector terminals
while turning FR wheel at a speed of 1 RPS:
Is voltage between EHCU connector terminals 4 and 5 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 resistance between connector (C-41) terminals 1 and 2 within
1.3k - 1.9k ohms?Connector is
faulty, or open or
short circuit of
harness between
wheel speed
sensor connector
and EHCU.
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 and ensure all components are
properly mounted.
Was this step finished?Repeat the “Basic
diagnostic flow
chart.”
Go to Step 3
Chart C-1-3 RL Sensor Output Inspection Procedure
StepActionYe sNo
11. Turn the key off.
2. Disconnect EHCU connector.
3. Jack up the vehicle with all four wheels off the ground.
Measure the AC voltage between EHCU connector terminals
while turning RL wheel at a speed of 1 RPS:
Is voltage between EHCU connector terminals 22 and 23 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 resistance between connector (F-3) terminals 1 and 2 within
1.3k - 1.9k ohms?Connector is
faulty, or open or
short circuit of
harness between
wheel speed
sensor connector
and EHCU.
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 and ensure all components are
properly mounted.
Was this step finished?Repeat the “Basic
diagnostic flow
chart.”
Go to Step 3

5A–59 BRAKE CONTROL SYSTEM
Chart C-1-4 RR Sensor Output Inspection Procedure
StepActionYe sNo
11. Turn the key off.
2. Disconnect EHCU connector.
3. Jack up the vehicle with all four wheels off the ground.
Measure the AC voltage between EHCU connector terminals
while turning RR wheel at a speed of 1 RPS:
Is voltage between EHCU connector terminals 2 and 3 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 resistance between connector (F-2) terminals 1 and 2 within
1.3k - 1.9k ohms?Connector is
faulty, or open or
short circuit of
harness between
wheel speed
sensor connector
and EHCU.
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 and ensure all components are
properly mounted.
Was this step finished?Repeat the “Basic
diagnostic flow
chart.”
Go to Step 3
Chart TC-1 Sensor Output Inspection Procedure (Use TECH 2)
StepActionYe sNo
11. Connect TECH 2.
2. While driving the vehicle, check the wheel speed of each
sensor by Data List.
Is the vehicle speed value is 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 3
Repair.
Go to Step 6
3While driving the vehicle, check the wheel speed of each sensor
by Data List.
Is the vehicle speed value is normal?
Go to Step 6Go to Step 4
4Check the sensor rotor.
Is the sensor rotor normal?
Go to Step 6
Replace sensor
rotor.
Go to Step 5
5While driving the vehicle, check the wheel speed of each sensor
by Data List.
Is the vehicle speed value is normal?
Go to Step 6
Repair harness or
connector
between EHCU
and speed
sensor.
Go to Step 6
6Reconnect all components, ensure all components are properly
mounted.
Was this step finished?Repeat the “Basic
diagnostic flow
chart.”
Go to Step 6

5B–1 ANTI–LOCK BRAKE SYSTEM
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. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 5B–2. . . . . . . . . . . . . . . . . . . . . . . . . . . .
G-Sensor 5B–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 5B–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 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–5. . . . . . . . . . . . . . . . . .
Installation 5B–5. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Rear Wheel Speed Sensor 5B–6. . . . . . . . . . . . . . .
Rear Wheel Speed Sensor and
Associated Parts 5B–6. . . . . . . . . . . . . . . . . . . . . .
Removal 5B–6. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 5B–6. . . . . . . . . . . . . . . . . .
Installation 5B–6. . . . . . . . . . . . . . . . . . . . . . . . . . . .
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.CAUTION: Replace all components included in
repair kits used to service this system. Lubricate
rubber parts with clean, fresh brake fluid to ease
assembly. Do not use shop air with in–line
lubricators on brake parts, as damage to rubber
components may result. If any hydraulic component
is removed or brake line disconnected, it may be
necessary to bleed part or all of the brake system.
NOTE: The use of rubber hoses or parts other than those
furnished specifically for the Anti–lock Brake System may
lead to functional problems requiring major overhaul.

5B–4ANTI–LOCK BRAKE SYSTEM
Front Wheel Speed Sensor
Front Wheel Speed Sensor and Associated Parts
350RW012
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 bolts (1) and
caliper fixing bolt (2) from caliper side speed sensor
cable bracket (3).
350RW010
5. Remove speed sensor.

5B–6ANTI–LOCK BRAKE SYSTEM
Rear Wheel Speed Sensor
Rear Wheel Speed Sensor and Associated Parts
350RW008
Legend
(1) Speed Sensor Connector
(2) Sensor Cable Fixing Bolt(3) Clip (11 pieces)
(4) Speed Sensor
(5) Sensor Fixing Bolt
Removal
1. Remove speed sensor connector.
2. Remove clip.
3. Remove sensor cable fixing bolt.
4. Remove sensor fixing bolt.
5. Remove speed sensor.
350RS035
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, and replace the
speed sensor if necessary.
3. Check the speed sensor cable for a short or an 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. If damaged replace the axle shaft assembly.
Refer to Front Hub and Disc in Drive Shaft System
section.
Installation
1. Install the speed sensor and take care not to hit the
speed sensor pole piece during installation.
2. Install the sensor fixing bolt and tighten it to the
specified torque.
Torque : 18 Nꞏm (1.8kgꞏm/13 lb ft)
3. Install the sensor cable fixing bolt and tighten it to the
specified torque.
Torque : 24 Nꞏm (2.4kgꞏm/18 lb ft)
NOTE: Confirm that the cable is not twisted when
connecting the speed sensor cable.
4. Install clip.
5. Install speed sensor connector.