2002 ISUZU AXIOM ABS

4C±45 DRIVE SHAFT SYSTEM
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 front propeller shaft and universal joint,
refer to
Front Propeller Shaft in this section.
Diagnosis
ConditionPossible causeCorrection
Oil Leak At Front AxleWorn or defective oil seal.Replace the oil seal.
Front axle housing cracked.Repair or replace.
Oil Leak At Pinion ShaftToo much gear oil.Correct the oil level.
Oil seal worn or defective.Replace the oil seal.
Pinion flange loose or damaged.Tighten or replace.
Noises In Front Axle Drive Shaft
JointBroken or worn drive shaft joints and
bellows (BJ and DOJ).Replace the drive shaft joints and
bellows.
ªClankº When Accelerating From
ªCoastºLoose drive shaft joint to output shaft
bolts.Tighten.
Damaged inner drive shaft joint.Replace.
Shudder or Vibration During
Acceleration
Excessive drive shaft joint angle.Repair.
AccelerationWorn or damaged drive shaft joints.Replace.
Sticking spider assembly (inner drive
shaft joint).Lubricate or replace.
Sticking joint assembly (outer drive
shaft joint).Lubricate or replace.
Vibration At Highway SpeedsOut of balance or out of round tires.Balance or replace.
Front end out of alignment.Align.
Noises in Front AxleInsufficient gear oil.Replenish the gear oil.
Wrong or poor grade gear oil.Replace the gear oil.
Drive pinion to ring gear backlash
incorrect.Adjust the backlash.
Worn or chipped ring gear, pinion
gear or side gear.Replace the ring gear, pinion gear or
side gear.
Pinion shaft bearing worn.Replace the pinion shaft bearing.
Hub unit bearing worn.Replace the hub unit bearing.
Differential bearing loose or worn.Tighten or replace.
Wanders and PullsIncorrect front alignment.Adjust the front alignment.
Steering unit loose or worn.Tighten or replace.
Tire worn or improperly inflated.Adjust the inflation or replace.
Front or rear suspension parts loose
or broken.Tighten or replace.
Front Wheel ShimmyHub unit bearing worn.Replace.
Incorrect front alignment.Adjust the front alignment.
Worn ball joint or bush.Replace the ball joint or bush.
Steering unit loose or worn.Tighten or replace.
Tire worn or improperly inflated.Replace or adjust the inflation.
Shock absorber worn.Replace the shock absorber.

4C±47 DRIVE SHAFT SYSTEM
If abnormal conditions are discovered during
inspection, go to Step 6. If there are no abnormal
conditions, reassemble the front disc rotor and
caliper.
NOTE: Hub, wheel bearing and spindle is integrated to
the hub unit bearing so it must not be disassembled. If it
has abnormal rattle or noise, replace the hub unit bearing.
6. Remove the ABS sensor connector.
411R200004
Legend
(1) ABS Sensor Connector
(2) Bolt
7. Remove the 4 bolts fixing the hub unit bearing to the
knuckle.
Apply penetrating oil to the bearing and knuckle contact
surfaces if the surfaces are stuck together because of
rust.
8. Temporarily install long bolts to 2 of the fixing bolt
holes (the bolts must have the same diameter and
thread width).
9. Strike the long bolts with a hammer to loosen and
remove the hub unit bearing from the knuckle.
Take care not to drop the bearing.10. If necessary, replace the wheel pin in the following
manner.

Place hub on a suitable work surface and remove
wheel studs, as required, using a hammer.
411RS004
Inspection
Inspect the parts listed below for abrasion, breakage, and
other abnormal conditions.
Repair, or replace the parts as required.

Disc

Caliper

Wheel pin

Hub unit bearing

4C±48
DRIVE SHAFT SYSTEM
Reassembly
1. Install wheel pin.
411RS005

Place hub on a wood workbench or a block of wood
approx. 6º by 6º to protect the wheel stud ends and
threads.

Install wheel stud, using a hammer.
NOTE: Be sure wheel stud is started squarely and seats
completely.
2. Install the hub unit bearing to the knuckle.
Tighten the bolts to the specified torque.
Hub unit bearing bolt
Torque: 103+10 N´m (10.5 + 1 kg´m)
If there is rust on the bearing and knuckle contact
surfaces, use sandpaper to remove it before installation.
3. Install the ABS sensor connector.
4. Install the disc rotor.
5. Install the brake caliper to the bracket.
Refer to
Front disc caliper assembly in Section 5C of this
Manual.

4C±49 DRIVE SHAFT SYSTEM
Front Hub and Disc (4WD Model)
Disassembled View
411R200010
Legend
(1) Disc Rotor
(2) Hub Unit, Bearing(3) Wheel Pin
(4) ABS Sensor Ring
(5) Bolt
Disassembly
1. Move the transfer case lever to the 2WD position.
2. Raise the vehicle with a jack. Support the frame with
chassis stands.
3. Remove the brake caliper from the bracket. Secure
the caliper with a wire that it does not interfare with the
work process.Refer to
Front disc caliper assembly in Section 5C of this
Manual.
4. Remove the disk rotor.
Apply penetrating oil to the bearing and disc rotor contact
surfaces if the surfaces are stuck together because of
rust.
5. Inspect the hub unit bearing. Refer to
inspection
below.

4C±50
DRIVE SHAFT SYSTEM
6. Use a dial gauge to measure the bearing axial rattle.
Bearing axial rattle: 0.05 mm max
411R200002If abnormal conditins are discovered during
inspection, go to Step 7. If there are no abnormal
conditions, reassemble the front discrotor and
caliper.
NOTE: Hub, wheel bearing and spindle is integrated to
the hub unit bearing so it must not be disassembled. If it
has abnormal rattle or noize, replace the hub unit bearing.
7. Loosen the caulking around the front drive shaft nuts.
8. Remove the nuts and discard them (they cannot be
reused).
9. Remove the 4 bolts fixing the hub unit bearing to the
knuckle.
Apply penetrating oil to the bearing and knuckle contact
surfaces if the surfaces are stuck together because of
rust.
10. Temporarily install long bolts to 2 of the fixing bolt
holes (the bolts must have the same diameter and
thread width).
411R200012
Legend
(1) Bolt
11. Strike the long bolts with a hammer to loosen and
remove the hub unit bearing from the knuckle.

Take care not to strike the front drive shaft.

Take care not to drop the bearing.
12. Remove the ABS rotor sensor from the bearing.
13. If necessary, replace the wheel pin in the following
manner.

Place hub on a suitable work surface and remove
wheel studs, as required, using a hammer.
411RS004
Inspection
Inspect the parts listed below for abrasion, breakage, and
other abnormal conditions.
Repair or replace the parts as required.

Disc

Caliper

Drive shaft oil seal

ABS sensor rotor

Wheel pin

Hub unit bearing

4C±51 DRIVE SHAFT SYSTEM
Reassembly
1. Install the wheel pin.

Place hub on a wood workbench or a block of wood
approx. 6º by 6º to protect the wheel stud ends and
threads.

Install the wheel stud, using a hammer.
NOTE: Be sure wheel stud is started squarely and seats
completely.
411RS005
2. Install the ABS rotor sensor to the hub unit bearing.
Tighten the bolts to the specified torque.
ABS rotor sensor bolt
Torque: 18.7+5 N´m (1.9+0.5 kg´m)
3. Install the hub unit bearing to the knuckle. Tighten the
bolts to the specified torque.
Hub unit bearing bolt
Torque: 103+10 N´m (10.5+1 kg´m)
If there is rust on the bearing and knuckle contact
surfaces, use sandpaper to remove it before installation.
Take care not to push the front drive shaft and oil seal out
of position.
4. Hand tighten the front drive shaft nuts.
Use new nuts.
5. Install the disc rotor.
6. Install the brake caliper to the bracket.
Refer to
Front disc caliper assembly in Section 5C of this
Manual.7. Tighten the front drive shaft nuts to the specified
torque.
Front drive shaft nut
Torque: 245+19.6 N´m (25+2 kg´m)
411R200005
8. Caulk the front drive shaft nuts.
The caulking must be free of cracks.
411R200006

4C±70
DRIVE SHAFT SYSTEM
Phasing
The propeller shaft is designed and built with the yoke
lugs (ears) in line with each other. This design produces
the smoothest running shaft possible, called
phasing.Vibration can be caused by an out±of±phase
propeller shaft.The propeller shaft will absorb vibrations
from speeding up and slowing down each time the
universal joint spins.This vibration would be the same as
a person snapping a rope and watching the ºwaveº
reaction flow to the end.A propeller shaft working in phase
would be similar to two persons snapping a rope at the
same time, and watching the ºwavesº meet and cancel
each other out.In comparison, this would be the same as
the universal joints on a propeller shaft.A total
cancellation of vibration produces a smooth flow of power
in the driveline.It is very important to apply a reference
mark to the propeller shaft before removal, to assure
installation alignment.
Universal Joint
401RW015
Legend
(1) Spider
(2) Yoke
A universal joint consists of two Y-shaped yokes
connected by a crossmember called a spider.
The spider is shaped like a cross. Universal joints are
designed to handle the effects of various loadings and
front or rear axle windup during acceleration. Within the
designed angle variations, the universal joint will operate
efficiently and safely. When the design angle is changed
or exceeded the operational life of the joint may decrease.
The bearings used in universal joints are of the needle
roller type. The needle rollers are held in place on the
trunnions by round bearing cups. The bearing cups are
held in the yokes by snap rings.

5A±1
BRAKE CONTROL SYSTEM
AXIOM
BRAKES
CONTENTS
Brake Control System 5A±1. . . . . . . . . . . . . . . . . . . .
Anti±lock Brake System 5B±1. . . . . . . . . . . . . . . . . .
Power±assisted Brake System 5C±1. . . . . . . . . . . .
Parking Brakes (4x4 Model) 5D1±1. . . . . . . . . . . . . .
Parking Brakes (4x2 Model) 5D2±1. . . . . . . . . . . . . .
Brake Control System
CONTENTS
Service Precaution 5A±2. . . . . . . . . . . . . . . . . . . . . .
General Description 5A±3. . . . . . . . . . . . . . . . . . . . .
Functional Description 5A±4. . . . . . . . . . . . . . . . .
System Components 5A±10. . . . . . . . . . . . . . . . . . .
Electronic Hydraulic Control Unit (EHCU) 5A±10.
ABS Warning Light 5A±10. . . . . . . . . . . . . . . . . . . .
Wheel Speed Sensor 5A±10. . . . . . . . . . . . . . . . . .
G-Sensor 5A±10. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Normal and Anti-lock Braking 5A±10. . . . . . . . . . .
Brake Pedal Travel 5A±10. . . . . . . . . . . . . . . . . . . .
Acronyms and Abbreviations 5A±11. . . . . . . . . . . .
General Diagnosis 5A±11. . . . . . . . . . . . . . . . . . . . . . .
General Information 5A±11. . . . . . . . . . . . . . . . . . . .
ABS Service Precautions 5A±11. . . . . . . . . . . . . . .
Computer System Service Precautions 5A±11. . .
General Service Precautions 5A±11. . . . . . . . . . . .
Note on Intermittents 5A±11. . . . . . . . . . . . . . . . . . .
Test Driving ABS Complaint Vehicles 5A±12. . . . .
ªABSº Warning Light 5A±12. . . . . . . . . . . . . . . . . . .
Normal Operation 5A±12. . . . . . . . . . . . . . . . . . . . .
Tech 2 Scan Tool 5A±13. . . . . . . . . . . . . . . . . . . . . .
DATA LIST 5A±16. . . . . . . . . . . . . . . . . . . . . . . . . . .
ACTUATOR TEST 5A±17. . . . . . . . . . . . . . . . . . . . .
Tech 2 Service Bleed 5A±21. . . . . . . . . . . . . . . . . .
Basic Diagnostic Flow Chart 5A±22. . . . . . . . . . . .
Basic Inspection Procedure 5A±23. . . . . . . . . . . . .
EHCU Connector Pin-out Checks 5A±24. . . . . . . . .
Circuit Diagram 5A±25. . . . . . . . . . . . . . . . . . . . . . .
Connector List 5A±28. . . . . . . . . . . . . . . . . . . . . . . .
Part Location 5A±29. . . . . . . . . . . . . . . . . . . . . . . . .
Symptom Diagnosis 5A±30. . . . . . . . . . . . . . . . . . . . .
Chart A-1 ABS Works Frequently But
Vehicle Does Not Decelerate 5A±30. . . . . . . . . . .
Chart TA-1 ABS Works Frequently But
Vehicle Does Not Decelerate
(Use TECH 2) 5A±31. . . . . . . . . . . . . . . . . . . . . . . .
Chart A-2 Uneven Braking Occurs While
ABS Works 5A±31. . . . . . . . . . . . . . . . . . . . . . . . . . .
Chart TA-2 Uneven Braking Occurs While
ABS Works (Use TECH 2) 5A±31. . . . . . . . . . . . . Chart A-3, TA-3 The Wheels Are Locked 5A±32.
Chart A-4 Brake Pedal Feed Is Abnormal 5A±32.
Chart A-5, TA-5 Braking Sound
(From EHCU) Is Heard While Not Braking 5A±33
Diagnostic Trouble Codes 5A±34. . . . . . . . . . . . . . . .
Diagnosis By ªABSº Warning Light
Illumination Pattern 5A±36. . . . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Codes (DTCs) 5A±37. . . . . . .
Chart B-1 With the key in the ON position
(Before starting the engine). Warning light
(W/L) is not activated. 5A±39. . . . . . . . . . . . . . . . .
Chart B-2 CPU Error (DTC 14 (Flash out) /
C0271, C0272, C0273, C0284 (Serial
communications)) 5A±39. . . . . . . . . . . . . . . . . . . . .
Chart B-3 Low or High Ignition Voltage
(DTC 15 (Flash out) / C0277, 0278 (Serial
communications)) 5A±40. . . . . . . . . . . . . . . . . . . . .
Chart B-4 Excessive Dump Time (DTC 17
(Flash out) / C0269 (Serial
communications)) 5A±40. . . . . . . . . . . . . . . . . . . . .
Chart B-5 Excessive Isolation Time
(DTC 18 (Flash out) / C0274
(Serial communications)) 5A±40. . . . . . . . . . . . . . .
Chart B-6 G-Sensor Output Failure
(DTC 21 (Flash out) / C0276
(Serial communications)) 5A±41. . . . . . . . . . . . . . .
Chart B-7 Brake Switch Failure
(DTC 22 (Flash out) / C0281
(Serial communications)) 5A±41. . . . . . . . . . . . . . .
Chart B-8 2WD Controller in 4WD Vehicle
Controller (DTC 13 (Flash out) / C0285
(Serial communications)), 4WD State Input
Signal Failure (DTC 24 (Flash out) / C0282
(Serial communications)) 5A±42. . . . . . . . . . . . . . .
Chart B-9 Pump Motor Failure
(DTC 32 (Flash out) / C0267, C0268
(Serial communications)) 5A±42. . . . . . . . . . . . . . .
Chart B-10 EHCU Valve Relay Failure
(DTC 35 (Flash out) / C0265, C0266
(Serial communications)) 5A±43. . . . . . . . . . . . . . .
Chart B-11 FL Isolation Solenoid Coil Failure
(DTC 41 (Flash out) / C0245, C0247
(Serial communications)) 5A±43. . . . . . . . . . . . . . .
Chart B-12 FL Dump Solenoid Coil Failure
(DTC 42 (Flash out) / C0246, C0248
(Serial communications)) 5A±43. . . . . . . . . . . . . . .