ECU ISUZU AXIOM 2002 Service Repair Manual

SECTION TABLE OF CONTENTS
GENERAL INFORMATION
0AGeneral Information
0BMaintenance and Lubrication
WORKSHOP MANUAL
HEATING, VENTILATION AND AIR
CONDITIONING
1AHVAC System
STEERING
2APower-Assisted System
AXIOM
(UPR/S)SUSPENSION
3CFront Suspension
3DRear Suspension
3EWheel and Tire System
3FIntelligent Suspension System
DRIVELINE/AXLE
4A1Differential (Front)
4A2Differential (Rear)
4B1Driveline Control System
4B2Driveline Control System (TOD)
4CDrive Shaft System
4D2Transfer Case (TOD)
FOREWORD
This manual includes special notes, impor tant points, service data,
precautions, etc. That are needed for the maintenance, adjustments,
service, removal and installation of vehicle components.
All information, illustrations and specifications contained in this manual
are based on the latest product information available at the time of
publication.
All rights are reserved to make changes at any time without notice.
Arrangement of the material is shown in the table of contents on the
right-hand side of this page. A black spot on the first page of each
section can be seen on the edge of the book below each section title.
These point to a more detailed table of contents preceding each
section.BRAKE
5ABrake Control System
5BAnti-Lock Brake System
5CPower-Assisted Brake System
5D1Parking Brake System (4´4 model)
5D2Parking Brake System (4´2 model)
ENGINE
6AEngine Mechanical
6BEngine Cooling
6CEngine Fuel
6D1Engine Electrical
6D2Ignition System
6D3Starting and Charging System
6EDriveability and Emissions
6FEngine Exhaust
6GEngine Lubrication
6HEngine Speed Control System
6JInduction
TRANSMISSION
7AAutomatic Transmission
7A1Transmission Control System
BODY AND ACCESSORIES
8ALighting System
8BWiper/Washer System
This manual applies to 2002 models.8CEnter tainment
8DWiring System
8EMeter and Gauge
8FBody Structure
8GSeats
8HSecurity and Locks
8ISun Roof/Convertible Top
8JExterior/Interior Trim
RESTRAINTS
9ASeat Belt System
9JSupplemental Restraint System (Air Bag System)
9J1Restraint Control System
CONTROL SYSTEM
10ACruise Control System

HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
1A±17
7. Remove rear heater duct.

Remove foot rest carpet and 3 clips.
8. Remove defroster nozzle.
Installation
To install, follow the removal steps in the reverse order,
noting the following point:
1. Connect each duct and nozzle securely leaving no
clearance between them and making no improper
matching.

1A±24
HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
Diagnosis
Air Conditioning Cycle Diagnosis
ConditionPossible causeCorrection
No cooling or insufficient cooling.Magnetic clutch does not run.Refer to ªMagnetic Clutch Diagnosisº
in this section.
Compressor is not rotating properly.
Drive belt is loose or broken.Adjust the drive belt to the specified
tension or replace the drive belt.
Compressor is not rotating properly.
Magnetic clutch face is not clean and
slips.Clean the magnetic clutch face or
replace.
Compressor is not rotating properly.
Incorrect clearance between
magnetic drive plate and pulley.Adjust the clearance. Refer to
Compressor in this section.
Compressor is not rotating properly.
Compressor oil leaks from the shaft
seal or shell.Replace the compressor
Compressor is not rotating properly.
Compressor is seized.Replace the compressor
Insufficient or excessive charge of
refrigerant.Discharge and recover the
refrigerant. Recharge to the
specified amount.
Leaks in the refrigerant system.Check the refrigerant system for
leaks and repair as necessary.
Discharge and recover the
refrigerant. Recharge to the
specified amount.
Condenser is clogged or insufficient
radiation.Clean the condenser or replace as
necessary.
Temperature control link unit of the
heat unit is defective.Repair the link unit.
Unsteady operation due to a foreign
substance in the expansion valve.Replace the expansion valve.
Poor operation of the electronic
thermostat.Check the electronic thermostat and
replace as necessary.
Insufficient velocity of cooling air.Evaporator clogged or frosted.Check the evaporator core and
replace or clean the core.
Air leaking from the cooling unit or air
duct.Check the evaporator and duct
connection, then repair as
necessary.
Blower motor does not rotate
properly.Refer to Fan Control Lever (Fan
Switch) Diagnosis in this section.
*For the execution of the charging and discharging
operation in the table above, refer to
Recovery,
Recycling, Evacuating and Charging in this section.

1A±32
HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
Repair Of Refrigerant Leaks
Refrigerant Line Connections
Install new O-rings, if required. When disconnecting or
connecting lines, use two wrenches to prevent the
connecting portion from twisting or becoming damaged.
852R200001When connecting the refrigerant line at a block joint,
securely insert the projecting portion of the joint portion
into the connecting hole on the unit side and secure with a
bolt. Apply the specified compressor oil to the O-rings
prior to connecting.
CAUTION: Compressor (PAG) oil to be used varies
according to the compressor model. Be sure to apply
oil specified for the model of compressor.
850RW002
O-rings (2) must be fitted in the groove (1) of refrigerant
line.
850RW003Insert the nut into the union.
First, tighten the nut by hand as much as possible, then
tighten the nut to the specified torque.
850RW004

1A±42
HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
Condenser Fan Motor
Condenser Fan Motor and Associated Parts
875R200016
Legend
(1) Condenser Fan Assembly
(2) Condenser Air Guide
(3) Front Bumper Assembly(4) Condenser Fan Motor
(5) Shroud
(6) Fan
(7) Horn (RH)
Removal
1. Disconnect the battery ground cable.
2. Remove the front bumper assembly.

Refer to the
Front Bumper in Body Structure
section.
3. Remove the condenser air guide.
4. Remove the horn (RH).
5. Remove the condenser fan assembly.

Disconnect the fan motor connector and remove
the 3 fixing bolts.
6. Remove the shroud.

Remove the 3 fixing nuts.

Loosen the condenser fixing nut and disconnect the
fan motor connector from bracket.
7. Remove the fan.

Remove the fan fixing C-ring and plate.
8. Remove the condenser fan motor.
Installation
To install, follow the removal steps in the reverse order,
noting the following point.
1. Route the fan motor harness in its previous position,
and fix it securely with clip and bracket.

POWER±ASSISTED STEERING SYSTEM2A±11
4. Bleed the system. Refer to Bleeding the Power
Steering System
in this section.
5. Start the engine and check the fluid level. Add power
steering fluid if required. When the engine is at
normal operating temperature, increase engine
speed to 1500 rpm.
CAUTION: Do not leave shutoff valve fully closed
for more than 5 seconds, as the pump could become
damaged internally.
6. Fully close the shutoff valve. Record the highest
pressures.

If the pressure recorded is within 9300±9800 kPa
(1350±1420 psi), the pump is functioning within its
specifications.

If the pressure recorded is higher than 9800 kPa
(1420 psi), the valve in the pump is defective.

If the pressure recorded is lower than 9300 kPa
(1350 psi), the valve or the rotating group in the
pump is defective.
7. If the pump pressures are within specifications, leave
the valve open and turn (or have someone else turn)
the steering wheel fully in both directions. Record the
highest pressures and compare with the maximum
pump pressure recorded in step 6. If this pressure
cannot be built in either side of the power steering
unit, the power steering unit is leaking internally and
must be replaced.
8. Shut the engine off, remove the testing gauge.
9. Reconnect the pressure hose, check the fluid level
and make the needed repairs.
10. If the problem still exists, the steering and front
suspension must be thoroughly examined.
Maintenance
The hydraulic system should be kept clean and fluid level
in the reservoir should be checked at regular intervals and
fluid added when required. Refer to
Recommended
Fluids and Lubricants in General Information
section for
the type of fluid to be used and the intervals for filling.
If the system contains some dirt, flush it as described in
this section. If it is exceptionally dirty, the pump must be
completely disassembled before further usage. (The
steering unit cannot be disassembled.)
All tubes, hoses, and fittings should be inspected for
leakage at regular intervals. Fittings must be tight. Make
sure the clips, clamps and supporting tubes and hoses
are in place and properly secured.
Power steering hoses and lines must not be twisted,
kinked or tightly bent. Air in the system will cause spongy
action and noisy operation. When a hose is disconnected
or when fluid is lost, for any reason, the system must be
bled after refilling. Refer to
Bleeding the Power Steering
System
in this section.

Inspect belt for tightness.

Inspect pulley for looseness or damage. The pulley
should not wobble with the engine running.

Inspect hoses so they are not touching any other
parts of the vehicle.

Inspect fluid level and fill to the proper level.
Fluid Level
1. Run the engine until the power steering fluid reaches
normal operating temperature, about 55
C (130
F),
then shut the engine off.
2. Check the level of fluid in the reservoir.
3. If the fluid level is low, add power steering fluid as
specified in General Information to the proper level
and install the receiver cap.
4. When checking the fluid level after the steering
system has been serviced, air must be bled from the
system. Refer to
Bleeding the Power Steering
System
in this section.
Bleeding The Power Steering System
When a power steering pump or unit has been installed,
or an oil line has been disconnected, the air that has
entered the system must be bled out before the vehicle is
operated. If air is allowed to remain in the power steering
fluid system, noisy and unsatisfactory operation of the
system may result.
Bleeding Procedure
When bleeding the system, and any time fluid is added to
the power steering system, be sure to use only power
steering fluid as specified in General Information.
1. Fill the pump fluid reservoir to the proper level and let
the fluid settle for at least two minutes.
2. Start the engine and let it run for a few seconds. Do
not turn the steering wheel. Then turn the engine off.
3. Add fluid if necessary.
4. Repeat the above procedure until the fluid level
remains constant after running the engine.
5. Raise and support the front end of the vehicle so that
the wheels are off the ground.
6. Start the engine. Slowly turn the steering wheel right
and left, lightly contacting the wheel stops.
7. Add power steering fluid if necessary.
8. Lower the vehicle, set the steering wheel at the
straight forward position after turning it to its full steer
positions 2 or 3 times, and stop the engine.
9. Check the fluid level and refill as required.
10. If the fluid is extremely foamy, allow the vehicle to set
a few minutes, then repeat the above procedure.
Flushing The Power Steering System
1. Raise and support the front end of the vehicle off the
ground until the wheels are free to turn.
2. Remove the fluid return line at the pump inlet
connector and plug the connector port on the pump.
Position the line toward a large container to catch the
draining fluid.
3. While running the engine at idle, fill the reservoir with
new power steering fluid. Turn the steering wheel in
both directions. Do not contact or hold the steering
wheel to the wheel stops. This will cause the pump to
go to pressure relief mode, which may cause a
sudden fluid overflow at the reservoir.

2A±46
POWER±ASSISTED STEERING SYSTEM
13. Remove the combination switch assembly with SRS
coil.
825RW288
14. Remove snap ring.
15. Remove cushion rubber.
16. Remove shift lock cable (For A/T).
17. Disconnect the starter switch harness connector
located under the steering column, then remove lock
cylinder assembly.
18. Apply a setting mark across the second steering shaft
and transfer gear assembly to reassemble the parts
in their original position, then remove the steering
column assembly and second steering shaft.
NOTE: A setting mark can be easily made if the shaft is
withdrawn a little by loosening the steering shaft universal
joint.
431RW009
Inspection
If the abnormal conditions are found through inspection,
replace the steering column assembly.
Column Capsule
Check capsules on steering column bracket assembly; all
must be securely seated in bracket slots and checked for
any loose conditions when pushed or pulled by hand.
431RW030Check clearance between capsule and bracket. If must
be within 1mm (0.039 in).
431RW031

2A±48
POWER±ASSISTED STEERING SYSTEM
Tilt Mechanism
Tilt mechanism should moves smoothly.
While locked the tilt mechanism, be sure the steering
column latch securely by pushing the steering wheel
upward and downward.
Installation
1. Pass through the steering column assembly to the
dash panel hole.
Temporary tightening the steering column bolt(cross
beam).
2. Tighten the steering column bolts(dash panel) to the
specified torque.
Torque: 20 N´m (14 lb ft)
3. Tighten the steering column nuts (cross beam) to the
specified torque.
Torque: 17 N´m (12 lb ft)
4. Install the universal joint assembly to the transfer
gear assembly align the setting marks made at
removal.
Then tighten the universal joint bolt.
Torque: 31 N´m (23 lb ft)
5. Install the second steering shaft to the universal joint
assembly, then tighten the universal joint bolt to the
specified torque.
Torque: 31 N´m (23 lb ft)
6. Install lock cylinder assembly.
7. Install shift lock cable (For A/T).
8. Install cushion rubber.
9. Install snap ring.
10. Install combination switch and SRS coil assembly.
After installation of combination switch assembly,
connect the combination switch wiring harness
connector and the SRS 2-way connector located
under the steering column.11. Turn the SRS coil counter clockwise to full, return
about 3 turns and align the neutral mark.
CAUTION: Turn the SRS coil counter clockwise
until a resistance is felt or damage to the SRS coil
may occur from over turning.
825RW016
12. When installing the steering column cover, be sure to
route each wire harness as illustrated so that the
harnesses do not catch any moving parts.
825RW017
Legend
(1) Steering Column Cover
(2) Starter Switch Harness
(3) Combination Switch Harness
(4) Inflator Module Harness

3C±2FRONT SUSPENSION
General Description
The front suspension is designed to allow each wheel to
compensate for changes in the road surface level without
greatly affecting the opposite wheel. Each wheel is
independently connected to the frame by a steering
knuckle, ball joint assemblies, and upper and lower
control arms. The front wheels are held in proper
relationship to each other by two tie-rods which are
connected to steering arms on the knuckles, and to a
steering unit.
All models have a front suspension system consisting of
control arms, stabilizer bar, shock absorber and a torsion
bar. The front end of the torsion bar is attached to the
lower control arm. The rear of the torsion bar is mounted
into a height control arm at the crossmember. Vehicle trim
height is controlled by adjusting this arm.
Shock absorbers are mounted between the brackets on
the frame and the lower control arms. The lower portion ofeach shock absorber is attached to the lower control arm.
The upper portion of each shock absorber extends
through a frame bracket and is secured with two rubber
bushings, two retainers and a nut.
Ball joint assemblies are bolted to the outer end of the
upper and lower control arm and are attached to the
steering knuckle.
The inner ends of the upper control arm have pressed in
bushings. Bolts, passing through the bushing, attach the
control arm to the frame. The inner ends of the lower
control arm are attached to the frame by bolts passing
through the bushings.
Side roll of the front suspension is controlled by a spring
steel stabilizer bar. It is mounted in rubber bushings,
which are held to the frame by brackets. The ends of the
stabilizer bar are connected to the lower control arms by
links.
Diagnosis
ConditionPossible causeCorrection
Vehicle PullsMismatched or uneven tires.Replace tire.
Tires not adequately inflated.Adjust tire pressure.
Broken or sagging springs.Replace spring.
Radial tire lateral force.Replace tire.
Improper wheel alignment.Adjust wheel alignment.
Brake dragging in one wheel.Repair brake.
Loose, bent or broken front or rear
suspension parts.Tighten or replace the appropriate
suspension part(s).
Faulty shock absorbers.Replace shock absorber.
Parts in power steering valve
defective.Replace power steering unit.
Abnormal or Excessive Tire WearSagging or broken spring.Replace spring.
Tire out of balance.Balance or replace tire.
Improper wheel alignment.Check front end alignment.
Faulty shock absorber.Replace shock absorber.
Hard driving.Replace tire.
Overloaded vehicle.Replace tire and reduce load.
Tires not rotated periodically.Replace or rotate tire.
Worn or loose road wheel bearings.Replace wheel bearing.
Wobbly wheel or tires.Replace wheel or tire.
Tires not adequately inflated.Adjust the pressure.
Wheel HopBlister or bump on tire.Replace tire.
Improper shock absorber operation.Replace shock absorber.

DIFFERENTIAL (FRONT) 4A1±6
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.
412RW057
12. Remove the tie-rod end from the knuckle. Refer to
Power Steering Unit in Steering Section.
13. Disconnect the hose of the shift on the fly.
14. Disconnect the actuator connector.
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.
410RW008
17. Support the differential case by the jack.
18. Remove the front axle mounting bolts and nuts, lower
the jack slowly. Remove the left side drive shaft end
from the knuckle, then lower the axle assembly from
the vehicle.
CAUTION:
1. Make sure the axle assembly is supported
securely when performing repairs.
2. Do not damage the power steering unit when
performing the repairs.
3. Do not damage the shift±on±the fly hose bracket
when performing the repairs.
Installation
1. Support the differential case with a jack.
2. Jack up the front drive axle assembly, install the left
side drive shaft to the knuckle, then install the mount
bolts and nuts.
CAUTION:
1. Do not damage the power steering unit when
performing the repairs.
2. Do not damage the shift±on±the fly hose bracket
when performing the repairs.
3. When installing the drive shaft to the knuckle, be
careful not to damage the oil seal inside of the
knuckle.