ESP ISUZU TROOPER 1998 Service User Guide

SERVICE INFORMATION 00 – 7
Problem Possible Cause Correction
POWER STEERING SYSTEM
HISSING NOISE
There is some noise in all power steering systems. One of the most common is a hissing sound when the
steering wheel is fully turned and the car is not moving. This noise will be most evident when the wheel is
operated while the brakes are applied. There is no relationship between this noise and steering
performance. Do not replace the valve unless the "hissing" noise is extremely objectionable. A replacement
valve will also have a slight noise, and is not always a cure for the condition.
Rattle or Chucking Noise
Poor Return of Steering
Wheel to Center
Momentary Increase in
Effort When Turning
Wheel Fast to Right or
Left
Steering Wheel Surges or
Jerks When Turning
Especially During Parking
Excessive Wheel Kick
Back or Loose Steering
Hard Steering or Lack of
Power Assist1. Pressure hose touching other parts of
vehicle.
2. Tie rod ends loose.
3. Loose steering gear mounting.
4. Steering gear misadjustment.
1. Improper front wheel alignment.
2. Wheel bearing worn.
3. Tie rod end binding.
4. Ball joint binding.
5. Tight or frozen steering shaft bearing.
6. Steering gear misadjustment.
7. Sticky or plugged steering gear valve.
8. Entry of air in the power steering
system.
1. High internal leakage.
2. Power steering fluid level low.
1. Insufficient pump pressure.
2. Sticky steering gear valve.
3. Power steering fluid level low.
1. Air in system.
2. Tie rod end loose.
3. Wheel bearing worn.
1. Sticky steering gear valve.
2. Insufficient pump pressure.
3. Excessive internal pump leakage.
4. Excessive internal steering gear
leakage.
5. Power steering fluid level low.Adjust hose position. Do not
bend tubing by hand.
Tighten or replace tie rod end.
Tighten steering gear
mounting.
Check and adjust steering gear
preload.
Adjust front wheel alignment.
Replace front wheel bearing.
Replace tie rod end.
Replace ball joint.
Replace steering assembly.
Adjust the steering gear.
Repair or replace steering gear
valve.
Bleed the system.
Repair steering gear.
Replenish fluid.
Repair pump assembly.
Repair or replace steering gear.
Replenish fluid.
Bleed hydraulic system.
Tighten tie rod end.
Replace wheel bearing.
Repair or replace steering gear
valve.
Repair pump assembly.
Repair pump assembly.
Repair steering gear.
Replenish fluid.

3C – 8 FRONT SUSPENSION
2. Height Control Arm
Apply the setting marks to the height control arm and
torsion bar.
3. Torsion Bar
Apply the setting marks to the torsion bar and lower
control arm.
INSPECTION AND REPAIR
Make necessary correction or parts replacement if wear,
damage, corrosion or any other abnormal condition are
found through inspection.
Check the following parts:
•Torsion bar
•Height control arm
•Adjust bolt
•Rubber seat
INSTALLATION
3. Torsion Bar
Make sure the bars are on their correct respective
sides.
Apply grease to the serrated portions.

3E – 4 WHEELS AND TIRES
TIRES
REPLACEMENT
When replacement is necessary, the original metric size
should be used. Most metric tire sizes do not have exact
corresponding alphanumeric tire sizes. It is recommended
that new tires be installed in pairs on the same axle. If
necessary to replace only one tire, it should be paired with
tire having the most tread, to equalize braking traction.
CAUTION:
Do not mix different types of tires such as radial, bias and
bias-belted tires except in emergencies, because vehicle
handling may be seriously affected and may result in loss
of control.
TIRE MOUNTING
Remove valve cap on valve stem and deflate the tire.
Then use a tire changing machine to mount or dismount
tires.
Follow the equipment manufacturer’s instruction. Do not
use hand tools or tire lever alone to change tires as they
may damage the tire beads or wheel rim.
TIRE DISMOUNTING
Rim bead seats should be cleaned with a wire brush or
coarse steel wool to remove lubricants, and light rust.
Before mounting a tire, the bead area should be well
lubricated with an approved tire lubricant.
After mounting, inflate the tire to 196 kPa (28 psi) so that
beads are completely seated. Inflate the air to specified
pressure and install valve cap to the stem
WARNING:
NEVER STAND OVER TIRE WHEN INFLATING. BEAD MAY
BREAK WHEN BEAD SNAPS OVER RIM’S SAFETY HUMP
AND CAUSE SERIOUS PERSONAL INJURY.
NEVER EXCEED 240 kPa (35 psi) PRESSURE WHEN
INFLATING. IF 240 kPa (35 psi) PRESSURE WILL NOT
SEAT BEADS, DEFLATE, RE-LUBRICATE AND RE-INFLATE.
OVER INFLATION MAY CAUSE THE BEAD TO BREAK AND
CAUSE SERIOUS PERSONAL INJURY.
TIRE REPAIR
There are many different materials on the market used to
repair tires.
Manufacturers have published detailed instructions on
how and when to repair tires. These instructions can be
obtained from the tire manufacturer if they are not
included with the repair kit.
UNIT REPAIR

4A2A±30
DIFFERENTIAL (REAR 220mm)
3. After measuring dimensions of each of the above
sections, proceed with the adjustment in the following
manner:
Adjust the clearance to satisfy the equation below.
{(F ± B) + G ± H}=0.05 ± 0.20 mm
Also, select the thrust washers so that the
dimensional difference between the back surfaces of
the left and right pressure rings to the thrust washers
is 0.05mm or less.
Thickness : 1.5mm (0.059 in)
1.6 mm(0.063 in)
1.7 mm(0.067 in)
NOTE: When assembling the parts, apply recommended
gear oil sufficiently to each of the parts, especially, to the
contact surfaces and sliding surfaces.
1. Install Differential cage B.
2. Install Thrust washer.
3. Install Spring disc.

When assembling the spring disc, make sure the
mounting direction is correct as shown in figure.
425RS068
Legend
(1) Friction Plate
(2) Spring Disc
(3) Friction Disc
4. Inatall Spring disc.
5. Inatall Friction plate.
6. Inatall Friction disc.
7. Inatall Friction plate.
8. Inatall Friction disc.
9. Inatall Pressure ring.
10. Inatall Side gear.
11. Inatall Pinion and pinion shaft.
12. Inatall Side gear.
13. Inatall Pressure ring.
14. Inatall Friction disc.15. Inatall Friction plate.
16. Inatall Friction disc.
17. Inatall Friction plate.
18. Inatall Spring disc.

When assembling the spring disc, make sure the
mounting direction is correct.
19. Inatall Spring disc.
20. Inatall Thrust washer.
21. Inatall Differential cage A.
22. Inatall Screw.

Matching the guide marks of the differential cages A
and B, tighten the screws evenly in the diagonal
order.
425RS055

4B2±3 DRIVE LINE CONTROL SYSTEM (TOD)
detects the slip condition, determines the optimum torque
based on the feedback control logic, and increases the
torque to the front wheels.
The control unit uses the signal from the throttle position
sensor to predict the future vehicle condition and the
intention of the driver with respect to acceleration and
deceleration, and determines the initial torque distribution
using these data and the information from the speed
sensors.
In case of small circle turning in the parking lot, for
example, the control unit minimizes the clutch pressing
force restrict a braking phenomenon. When the ABS
becomes active, the control unit optimizes the clutch
pressing force to ensure stable braking.
TOD Indicator Control
The TOD indicator on the instrument panel informs the
driver of the current working status of the transfer unit.
The information consists of two items: the drive mode
(2H, TOD, 4L, transition) and the torque split status of the
TOD (torque distribution level). The indicator can display
occasional errors and corresponding error codes.

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±6
High-Low Planetary Gear Set
Establishes an auxiliary transmission mechanism. When
the transfer shift lever is set to the 2H or TOD position, the
reduction gear ratio is 1.000 and the corresponding
driving force is generated. When the transfer shift lever is
set to the 4L position, the reduction gear ratio is 2.480 and
the corresponding driving force is generated.
262RW030
4H and 4L Switches
Detects the shift position of the transfer from the
movement of the transfer lever and outputs signals to the
TOD control unit.
261RW002
Transfer Connector
Transmits the input and output signals of the speed
sensors, electromagnetic coil, and 4H and 4L switches to
the vehicle harness. A waterproof 12-pin type is used.
261RW046
TOD Indicator Lamps (on the instrument
panel)
Inform the following items.

Bulb check

Drive mode

ABS IN status

BRAKE ON status
821RW049

4B2±11 DRIVE LINE CONTROL SYSTEM (TOD)
The CHECK lamp also has the following functions.
D-G MAP recognition and display (The control unit
displays what type of vehicle, diesel or gasoline
vehicle, it recognizes.)
1. Short-circuit the self-diagnostic connector.
2. Turn on the starter switch. (Displays with respect to
the self-diagnosis begin to appear.)
NOTE: Do not start the engine.
3. Shift the transfer lever to the neutral position between
HIGH and 4L.
4. After all the conditions in 1 through 3 above are met,
set the throttle to the WOT (wide open throttle)
position (i.e., full open position). The display of the
self-diagnosis is temporarily suspended, and the
CHECK lamp begins to display that MAP is
recognized by the TPS (throttle position sensor)
according to the current conditions.NOTE: If the TPS has failed, this function might not work.
1. When the control unit recognizes the vehicle as
gasoline type, the CHECK lamp is turned on for five
seconds and this mode is repeated at an interval of
0.3 second.
2. When the control unit recognizes the vehicle as
diesel type, the CHECK lamp is turned off for five
seconds and this mode is repeated at an interval of
0.3 seconds.
3. Upon completion of step 4, the system resumes the
self-diagnosis. (The self-diagnosis is executed
from the beginning.)
5. Turn off the starter switch once. When above
conditions are met again in the future, the TPS MAP
control can be started.
C04RW010

4B2±13 DRIVE LINE CONTROL SYSTEM (TOD)
Indication Method of Trouble Code

Short-circuit terminal 8 of the self-diagnostic
connector to GND to display the trouble code on the
CHECK lamp.
810RW308

If no trouble codes exist, code ª12º is displayed
continuously.

If trouble codes exist, code ª12º is displayed three
times, and the trouble codes, starting from the smaller
code number, are displayed three times respectively.
C07RW013

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±34
Check flowTrouble codePhenomenonStandard
316The front speed sensor no pulse.Hi level : 4.5 ~ 6.0 V
Lo level : 0.7 ~ 2.0 V
Frequency (F) =
GAS: 832 Hz (at 50 km/h)
NOTE: Find the trouble in which the pulse corresponding
to the running speed is not input.
D04RW061

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±36
Check flowTrouble codePhenomenonStandard
427The rear speed sensor no pulse.Hi level : 4.5 ~ 6.0 V
Lo level : 0.7 ~ 2.0 V
Frequency (F) =
832 Hz (at 50 km/h)
NOTE: Find the trouble in which the pulse corresponding
to the running speed is not input.
D04RW060