1998 ISUZU TROOPER stop start

2A Ð 62 SUPPLEMENTAL RESTRAINT SYSTEM STEERING WHEEL & COLUMN
Use special tool. Remove the steering wheel.
Move the tires to the straight ahead position before
removing the steering wheel.
Steering wheel remover: 5-8840-0016-0 (J-29752)
CAUTION:
Never apply force to the steering wheel in direction of the
shaft by using a hammer or other impact tools in an
attempt to remove the steering wheel. The steering shaft
is designed as an energy absorbing unit.
6. Steering Column Cover
7. Combination Switch and SRS Coil Assembly
1) Disconnect the wiring harness connectors
located under the steering column.
2) Remove the combination switch assembly with
SRS coil.
NOTE:
The SRS coil is a part of the combination switch
assembly, which can not be replaced separately.
Therefore, be sure not to remove the SRS coil from
the combination switch assembly.
825RS046
INSTALLATION
Alignment mark
7. Combination Switch and SRS Coil Assembly
1) After installation of combination switch
assembly, connect the combination switch
wiring harness connector and the SRS 2way
connector located under the steering column.
2) Turn the SRS coil counterclockwise to full, return
about 3 turns and align the neutral mark.
CAUTION:
When turning the SRS coil counterclockwise to full, stop
turning if resistance is felt. Forced further turning may
damage to the cable in the SRS coil.
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Starter switch
harness
Combination
switch harness
Inflator module
harness
Setting cowl
(Lower)
6. Steering Column Cover
When installing the steering column cover, be sure to
route each wire harness as illustrated so that the
harnesses do not catch on any moving parts.
825RS048

SUPPLEMENTAL RESTRAINT SYSTEM STEERING WHEEL & COLUMN 2A – 67
INSTALLATION
11. Lock Cylinder Assembly
10. Shift Lock Cable (for A/T)
9. Cushion rubber
8. Snap ring
7. Combination Switch and SRS Coil Assembly
1) After installation of combination switch
assembly, connect the combination switch
wiring harness connector and the SRS 2way
connector located under the steering column.
2) Turn the SRS coil counterclockwise to full, return
about 3 turns and align the neutral mark.
CAUTION:
When turning the SRS coil counterclockwise to full, stop
turning if resistance is felt. Forced further turning may
damage to the cable in the SRS coil.
6. Steering Column Cover
When installing the steering column cover, be sure to
route each wire harness as illustrated so that the
harnesses do not catch on any moving parts.
5. Steering Wheel
Align the setting marks made when removing.
CAUTION:
Never apply force to the setting wheel in direction of the
shaft by using a hammer or other impact tools in an
attempt to remove the steering wheel. The steering shaft
is designed as an energy absorbing unit.
Tighten the steering wheel fixing nut to the specified
torque.
Steering Wheel Nut Torque N·m (kg·m/lb·ft)
34 (3.5 / 25)
Alignment mark
826RW027
Starter switch
harness
Combination
switch harness
Inflator module
harness
Setting cowl
(Lower)
825RS048

4B1±4
DRIVE LINE CONTROL SYSTEM (SHIFT ON THE FLY)
Inspection and Repair
Vacuum Piping
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1. Pull out the Hose A in figure and install a vacuum
gauge.
2. Plug up Hose B in figure to prevent the leak of
vacuum.
3. Start the engine and measure vacuum 2 or 3 minutes
afterward.
4. Repeat 1) and 2) but with Hose A plugged and Hose B
pulled out.
5. If vacuum measures ±400mmHg, or if it shows a
sudden drop immediately after engine stop, inspect
the hose, tank, and pipe for damage.
NOTE: Be careful not to permit the entry of dust and
water during inspection.
6. Pull out Hose D in above illustration.
7. Plug Hose E in above illustration.
8. Make sure that Hose D in above illustration is under
atmospheric pressure.
9. Pull out Hose E and plug Hose D, and make sure that
Hose E is under atmospheric pressure.
10. If Check 8) or 9) has revealed stoppage, check and
see that there is no bend, foreign matter in the hose or
in the filter. If there is trouble, repair or replace.Check Valve
C04RS004
1. Apply vacuum from the orange colored side(1).
Vacuum:±400mmHg
2. Check leakage of vacuum.
3. Make sure that vacuum cannot be applied from the
black colored side(2).

4B1±9 DRIVE LINE CONTROL SYSTEM (SHIFT ON THE FLY)
Retrial
The motor actuator starts transfer gear shifting after
signal from 4WD switch on instrument panel has been
received. But the shifting may be impossible in cold
weather or under high speed condition. When 2 seconds
have passed since transfer gear shifting started and the
transfer position switch dose not turn on (the gear
engagement is not completed), the motor reverses its
rotation for 1.2 seconds and tries again to shift transfergear. This procedure is repeated 3 times in maximum.
While this procedure, 4WD indicator lamp blinks by 2 Hz.
If the transfer position switch does not turn on after
aforementioned procedure has been repeated 3 times,
the gear shifting is stopped and 4WD indicator lamp's
blinking changes from 2Hz to 4Hz to notify driver that the
gear shifting is stopped. This blinking of indicator lamp
continues until 4WD switch is returned from 4WD to 2WD.
Time Chart of Shifting Under Severe Condition (re-
trial)
F04RW003

4B1±11 DRIVE LINE CONTROL SYSTEM (SHIFT ON THE FLY)
Functions of Indicator Lamp
Indication of vehicle condition : Indicator lamp is
controlled by 4WD control unit and shows vehicle
conditions as below.
Indicator
Vehicle condition4WD switchTransfer position
switchFront axle switch
Off2WDOff (Close)2WD (Open)2WD (Open)
On4WDOn (Open)4WD (Close)4WD (Close)
Blink (2Hz)OperatingOn (Open)4WD (Close)2WD (Open)
Off (Close)2WD (Open)4WD (Close)
Blink (4Hz)Stop operatingOn (Open)2WD (Open)2WD (Open)
Off (Close)4WD (Close)4WD (Close)
Bulb check :To check the bulb of indicator lamp, the
indicator lamp comes on when ignition key is turned on,
and goes off when the engine is started.
Retrials from 2WD to 4WD :In cold weather or under
high speed condition, the gear shifting (engagement)sometimes does not complete by 3 trials. In such case,
the indicator lamp inform driver of this incident as
aforementioned chart (shown at Retrial in Outline of shift
on the fly system).
Diagnosis
Before Judging That Troubles Occur
(Unfaulty mode)
When Switching from 2WD to 4WD
1.In case that blinking frequency of the 4WD
indicator changes from 2Hz to 4Hz.
When heavy synchronization load is needed, the
motor actuator tries the shifting transfer gear three
times including the activation shifting. While the
motor actuator tries shifting, the indicator blinks by
2Hz. If the third shifting fails, the indicator's blinking
changes from 2Hz to 4Hz at the same time that the
motor actuator shifted back to 2WD.
Heavy synchronization load occurs by:

extremely lower temperature.

higher speed, rotation difference of wheels during
cornering.
Solution 1: Operate again after stop the vehicle or
slow down.
2.In case that the 4WD indicator continues blinking
by 2Hz for more than 11.5 seconds.
When there is rotation difference of wheels or there
is phase difference between front wheels and axles,
it is difficult to connect front wheels to front axles. The
blinking by 2Hz shows that shifting the transfer gear
or connecting the front wheels is in the middle of
operating. In above case, the indicator's blinking by
2Hz shows that connecting the front wheels is not
completed (because the indicator's blinking changes
to 4Hz when the shifting transfer gear is impossible.).
And removal of rotation or phase difference make
connecting the front wheels possible.
Solution 2: When vehicle is running, drive
straight ahead while accelerating and
decelerating. When vehicle is at a stop, move the
vehicle forward and backward from 2 to 3 meters.When switching from 4WD to 2WD
1.In case that the 4WD indicator continues blinking
by 2Hz .
The 4WD indicator continues blinking by 2Hz until
both shifting the transfer gear and disconnecting the
front wheels are completed when switching 4WD to
2WD. When driveline is loaded with torsional torque,
the shifting transfer gear and disconnecting front
wheels are impossible. In this case, removal of
torsional torque on driveline make the shifting
transfer gear and disconnecting front wheels
possible.
Solution 3: When vehicle is running, drive
straight ahead while accelerating and
decelerating. When vehicle is at a stop, move the
vehicle forward and backward from 2 to 3 meters.
2.In case that the 4WD indicator's blinking changes
from 2Hz to 4Hz.
Check the position of transfer lever. Is it at ª4Lº
position? In view of the shifting mechanism of
transfer, the gear shifting from 4WD to 2WD at ª4Lº
condition is impossible.
Solution 4: Push the 4WD switch to 4WD, shift the
transfer lever to ªHighº position and re±operate
the 4WD switch to 2WD.

4B1±33 DRIVE LINE CONTROL SYSTEM (SHIFT ON THE FLY)
Inspection and Repair
Vacuum Piping
C04RW014
1. Pull out the Hose A in figure and install a vacuum
gauge.
2. Plug up Hose B in figure to prevent the leak of
vacuum.
3. Start the engine and measure vacuum 2 or 3 minutes
afterward.
4. Repeat 1) and 2) but with Hose A plugged and Hose B
pulled out.
5. If vacuum measures ±400mmHg, or if it shows a
sudden drop immediately after engine stop, inspect
the hose, tank, and pipe for damage.
NOTE: Be careful not to permit the entry of dust and
water during inspection.
6. Pull out Hose D in above illustration.
7. Plug Hose E in above illustration.
8. Make sure that Hose D in above illustration is under
atmospheric pressure.
9. Pull out Hose E and plug Hose D, and make sure that
Hose E is under atmospheric pressure.
10. If Check 8) or 9) has revealed stoppage, check and
see that there is no bend, foreign matter in the hose or
in the filter. If there is trouble, repair or replace.Check Valve
C04RS004
1. Apply vacuum from the orange colored side(1).
Vacuum:±400mmHg
2. Check leakage of vacuum.
3. Make sure that vacuum cannot be applied from the
black colored side(2).

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±12
Diagnosis
General Information Diagnosis
The troubles on TOD are classified into the group that can
be identified by the lighting status of the TOD indicator
lamps and those that can be recognized as abnormal
phenomena of the vehicle by the driver.
The troubles that can be identified by the lighting status of
the TOD indicator lamps are examined by the proceduresªDiagnosis from Trouble Codesº and ªTrouble Diagnosis
Depending on The Status of TOD indicatorº. The troubles
that can be recognized as abnormal phenomena of the
vehicle by the driver are examined by the procedure
ªDiagnosis from symptomº.
Self-diagnosis
The control unit has a function of self-diagnosis. If a
trouble occurs in the course of system startup, the control
unit blinks the CHECK lamp and saves the trouble code.
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NOTE: If an intermittent fault occurs, the control unit
stops blinking upon removal of the fault. The trouble code
is saved to the control unit.

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±14
How to Clear The Trouble Code
The trouble codes saved to the control unit can be deleted
by the following procedure if the starter switch is being in
the OFF position.
1. Shift the transfer lever to the neutral position between
HIGH and 4L, and short-circuit the self-diagnostic
connector.
NOTE: The neutral position between HIGH and 4L refers
to the point that turns off the TOD indicator lamps.
(However, be sure to check the position before
short-circuiting the self-diagnostic connector.)
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2. Turn on the starter switch while maintaining the state
of step 1, and step on the brake pedal five times within
five seconds from the first step on. (Note that ªfive
timesº includes the first step on). (The TOD indicator
lamps display the 4L mode whenever the brake pedal
is stepped on.)
3. If the conditions shown in steps 1 and 2 are met, clear
the trouble codes saved to the control unit. (After the
codes are completely deleted, the code 12 that
indicates the normal condition is continuously
displayed.)
Precautions on Diagnosis
Replacement of Control Unit
The control unit itself rarely fails. In most cases, the
harnesses have failed (e.q. short-circuit) to cause
secondary troubles. Other cases include that the cause
has been unknown due to intermittent occurrence of
troubles and the troubles are removed accidentally along
with replacement of control unit, resulting in misjudgment
of cause. Therefore, before replacing the control unit,
check the connector joints and whether the unspecified
current flows in the control unit due to short-circuit
between harnesses.Trouble Intermittently Observed
Troubles intermittently observed are mostly attributable
to temporary imperfect connection of harnesses and
connectors.
When such troubles are found, check the associated
circuit according to the following procedure.
1. Check whether improper connectors are plugged in
or connector terminals are completely engaged.
2. Check whether the terminals are deformed or
damaged. If yes, remove the deformation or damage
and connect the terminals securely.
3. It is likely that wires in the harness are falsely broken.
Therefore, in examination of failed harness circuit,
shake the harness for check to such extent that the
harness will not be damaged.
Test Run of Filed TOD Vehicle
If the TOD indicator lamps experienced faulty operation
even once in the past, the failed portion can be identified
by use of the procedure ªDiagnosis from Trouble Codesº
or ªTrouble Diagnosis Depending on The Status of TOD
Indicatorº. If the troubles that are only recognized as
abnormal phenomena of the vehicle by the driver are
observed, conduct the test run in the following procedure
to reproduce the faulty phenomena and diagnose the fault
for each phenomenon.
1. Start the engine, and check that the TOD indicator
lamps are turned on for about two seconds for initial
check; the CHECK lamp goes off; and the TOD
indicator lamps display the specified drive mode. (If
the CHECK lamp starts blinking, read the trouble
codes and identify the failed portion.)
2. While keeping the vehicle standstill, operate the 4WD
switch and shift the transfer lever to change the
modes: 2H mode"TOD mode"4L mode"TOD
mode"2H mode. Check that the TOD indicator
lamps correctly display the status whenever the
mode is changed. If the transition status is displayed
during the shift operation, run the vehicle a little to
complete shifting.
3. Slowly start the vehicle in the TOD mode, and add the
power to accelerate to at least 40 km/h and maintain
the speed for about two minutes. Apply the brake to
completely stop the vehicle. Repeat this test pattern
at least three times.
4. Turn the steering to the right end (or left end) in the
TOD mode, and slowly start the vehicle and make a
circle five times. Next, conduct the same test in the 2H
mode.
5. Slowly start the vehicle in the TOD mode, and
accelerate to at least 40 km/h. Keep the established
speed, carefully change the mode in the sequence
ªTOD mode"2H mode "TOD modeº while checking
that the shift is complete in each mode change. After
the test, apply the brake to completely stop the
vehicle.
6. Slowly start the vehicle in the TOD mode, and
accelerate to at least 40 km/h. Apply the brake
strongly so that the ABS works, and completely stop
the vehicle.