2004 ISUZU TF SERIES brakes

FRONT WHEEL DRIVE 4C1-15

Removal
1. Jack up the vehicle and support it using jack stand.
2. Remove the tire and wheel.
3. Remove the stone guard.
4. Remove the brake caliper fixing bolt and hang the caliper.
Refer to Disc Brakes in Brake section.
5. Remove the antilock brake system speed sensor.
Refer to Front Wheel Speed Sensor in Brake section.
6. Remove the hub and disc assembly.
Refer to Front Hub and Disc in this section.
7. Remove the propeller shaft, refer to Front Propeller Shaft in
this section.
8. Loosen the height control arm of the torsion bar, then
remove the torsion bar from lower control arm.
Refer to Torsion Bar in Suspension section.
9. Remove the suspension crossmember.
10. Remove the lower nut (1) of the stabilizer link.
11. Remove the lower bolt and nut (2) of the shock absorber.

12. Remove the tie-rod end from the knuckle.
Refer to Power Steering Unit in Steering Section.
13. Disconnect the breather hose of the front axle.
14. Disconnect the actuator connector. (With shift on the fly)
15. Remove the bolts and nuts of the lower control arm (Frame
side), then disconnect the lower control arm from frame.
16. Disconnect between the right side upper control arm and
the knuckle, then remove the knuckle with lower control
arm.
CAUTION :
When removing the knuckle, be careful not to damage the
oil seal inside of the knuckle.

FRONT WHEEL DRIVE 4C1-45
INSPECTION AND REPAIR
Make necessary correction or parts replacement if wear, damage or any other abnormal conditions are found
through inspection.
For inspection and servicing of disc caliper, and relative parts, and ABS parts, refer to section 5 Brakes.



Hub

Hub bearing

Bearing outer race


Disc


Oil seal


Knuckle spindle


ABS sensor rotor


Caliper



Visual Check
Check the following parts for wear, damage or other abnormal
conditions.

4C1-52 FRONT WHEEL DRIVE
INSPECTION AND REPAIR
Make necessary correction or parts replacement if wear, damage or any other abnormal conditions are found
through inspection.
For inspection and servicing of disc caliper, and relative parts, and ABS parts, refer to Section Brakes.




Hub


Hub bearing, oil seal


Knuckle spindle


Disc


Caliper


ABS sensor rotor

Cap, Hub flange, Shim, Snap ring



Visual Check
Check the following parts for wear, damage or other abnormal
conditions.

4C1-60 FRONT WHEEL DRIVE
INSPECTION AND REPAIR
Make necessary correction or parts replacement if wear, damage or any other abnormal conditions are found
through inspection.
For inspection and servicing of disc caliper, and relative parts, and ABS parts, refer to Section Brakes.




Hub

Hub bearing, oil seal


Knuckle spindle


Disc


Caliper


ABS sensor rotor


Cap, Hub flange, Shim, Snap ring


Free wheeling hub parts (Option)

Clutch, Knob, follower, inner, ring and
spring


Visual Check
Check the following parts for wear, damage or other abnormal
conditions.

WORKSHOP MANUAL

TF SERIES




BRAKES






SECTION 5

BRAKE CONTROL SYSTEM 5A-9

Pressure Isolation (Pressure Maintain)
The electronic-hydraulic control unit is activated when
the brakes are applied.
If the information from the wheel speed sensors
indicates excessive wheel deceleration (imminent
lockup), the first step in the anti-lock sequence is to
isolate the brake pressure being applied by the brake
pedal.
The microprocessor in the Control Unit sends a voltage
to the coil to energize and close the isolation valve.
This prevents any additional fluid pressure applied by
the brake pedal from reaching the wheel. With the
isolation valves closed, unnecessary increase in the
brake pressure is prevented.
C05L300013

BRAKE CONTROL SYSTEM 5A-19

System Components
Electronic Hydraulic Control Unit (EHCU), four Wheel
Speed Sensors, two Warning Lamps, and G-sensor.

Electronic Hydraulic Control Unit (EHCU)

The EHCU consists of ABS control circuits, fault
detector, and a fail-safe. It drives the EHCU according
to the signal from each sensor, cancelling ABS to return
to normal braking when a malfunction has occurred in
the ABS.
The EHCU has a self-diagnosing function which can
indicate faulty circuits during diagnosis.
The EHCU is mounted on the engine compartment rear
left side. It consists of a motor, solenoid valves fail safe
relay.
Solenoid Valves: Reduces or holds the caliper fluid
pressure for each front brake or both rear brakes
according to the signal sent from the EHCU.
Buffer chamber: Temporarily holds the brake fluid that
returns from the front and rear brake so that pressure
of front brake can be reduced smoothly.
Motor: Drives the pump according to the signal from
EHCU.
Fail safe Relay: When failure occurs in ABS.
The power supply to solenoid Valve is cut.

ABS Warning Lamp


825L300001
Vehicles equipped with the Anti-lock Brake System
have an amber “ABS” warning lamp in the instrument
panel. The “ABS” warning lamp will illuminate if a
malfunction in the Anti-lock Brake System is detected
by the Electronic Hydraulic Control Unit (EHCU). In
case of an electronic malfunction, the EHCU will turn
“ON” the “ABS” warning lamp and disable the anti-lock
braking function.

The “ABS” warning lamp will turn “ON” for
approximately three seconds after the ignition switch is
to the “ON” position.
If the “ABS” warning lamp stays “ON” after the ignition
switch is the “ON” position, or comes “ON” and stays
“ON” while driving, the Anti-lock Brake System should
be inspected for a malfunction according to the
diagnosis procedure.

Wheel Speed Sensor (WSS)
It consists of a sensor and a rotor. The sensor is
attached to the knuckle on the front wheels and to the
rear wheels.
The rotor is press-fit in the axle shaft.

G-Sensor
The G-sensor detects the vehicle deceleration speed
and sends a signal to the EHCU. In 4WD operation, all
four wheels may be decelerated in almost the same
phase, since all wheels are connected mechanically.
This tendency is noticeable particularly on roads with
low friction coefficient, and the ABS control is adversely
affected.
The G-sensor judges whether the friction coefficient of
road surface is low or high, and changes the EHCU's
operating system to ensure ABS and EBD control.

Normal and Anti-lock Braking
Under normal driving conditions, the Anti-lock Brake
System functions the same as a standard power
assisted brake system. However, with the detection of
wheel lock-up, a slight bump or kick-back will be felt in
the brake pedal. This pedal “bump” will be followed by a
series of short pedal pulsations which occurs in rapid
succession. The brake pedal pulsation will continue
until there is no longer a need for the anti-lock function
or until the vehicle is stopped. A slight ticking or
popping noise may be heard during brake applications
when the anti-lock features is being used.
When the anti-lock feature is being used, the brake
pedal may rise even as the brakes are being applied.
This is also normal. Maintaining a constant force on
the pedal will provide the shortest stopping distance.

ANTI-LOCK BRAKE SYSTEM 5B-1

SECTION 5B
BRAKES
ANTI-LOCK BRAKE SYSTEM
TABLE OF CONTENTS
PAGE
Service Precaution ...................................................................................................................... 5B – 2
Torque Specifications ................................................................................................................ 5B – 3
Electronic Hydraulic Control Unit ........................................................................................... 5B – 7
Electronic Hydraulic Control Unit and Associated Parts ............................................ 5B – 7
Removal .................................................................................................................................... 5B – 7
Installation ................................................................................................................................ 5B – 7
Front Wheel Speed Sensor ....................................................................................................... 5B – 8
Front Wheel Speed Sensor and Associated Parts ........................................................ 5B – 8
Removal .................................................................................................................................... 5B – 9
Inspection and Repair ........................................................................................................... 5B – 9
Installation ................................................................................................................................ 5B – 10
Rear Wheel Speed Sensor ........................................................................................................ 5B – 11
Rear Wheel Sensor and Associated Parts ....................................................................... 5B – 11
Removal .................................................................................................................................... 5B – 11
Inspection and Repair ........................................................................................................... 5B – 11
Installation ................................................................................................................................ 5B – 12
Front Speed Sensor Rotor ........................................................................................................ 5B – 13
Front Sensor Rotor and Associated Parts ....................................................................... 5B – 13
Removal .................................................................................................................................... 5B – 13
Inspection and Repair ........................................................................................................... 5B – 14
Installation ................................................................................................................................ 5B – 14
Rear Speed Sensor Rotor .......................................................................................................... 5B – 16
Rear Sensor Rotor and Associated Parts ........................................................................ 5B – 16
Removal .................................................................................................................................... 5B – 16
Inspection and Repair ........................................................................................................... 5B – 17
Installation ................................................................................................................................ 5B – 17
G-Sensor ........................................................................................................................................ 5B – 19
G-Sensor and Associated Parts ......................................................................................... 5B – 19