2004 ISUZU TF SERIES stop start

3B-46 POWER-ASSISTED STEERING SYSTEM


CAUTION:
When turning the SRS coil
counterclockwise to full, stop turning if resistance
is felt. Forced further turning may damage the cable
in the SRS coil.
(with SRS air bag)
826RW014
Legend
(1) Neutral mark





430RX005-X
16. Remove steering column cover.
17. Disconnect the wiring harness connectors located
under the steering column then remove combination
switch and SRS coil assembly. (with SRS air bag)
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. (with SRS air bag)
430R300014

Installation
1. Install the combination switch assembly with SRS
coil. (with SRS air bag)
2. Turn the SRS coil counterclockwise to full, return
about 3 turns and align the neutral mark. (with SRS
air bag)


3. Connect the wiring harness connectors located at
the base of steering column.
4. Install the air conditioning lower duct.
5. Install the steering column cover.
CAUTION:
When installing the steering column
cover, be sure to wire (through each harness) as
illustrated so that the harness starter switch,
combination switch and SRS coil may not catch
wiring.
(with SRS air bag)
825RS048

3B-60 POWER-ASSISTED STEERING SYSTEM

9. Turn the SRS coil counter clockwise to full, return
about 3 turns and align the neutral mark. (with SRS
air bag)
CAUTION: When turning the SRS coil counte
r
clockwise to full, stop turning if resistance is felt.
Forced further turning may damage to the cable in
the SRS coil.
826RW014
10. 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

11. Install steering wheel and align the setting marks
made when removing.
Refer to the adjustment method in case a mark is
not attached in this section.
NOTE: Confirm SRS and Horn harness connector is
fixed by the steering wheel.
RTW33BSH000601

CAUTION: Never apply force to the steering wheel in
direction of the shaft by using a hammer or othe
r
impact tools in an attempt to remove the steering
wheel. The steering shaft is designed as an energy
absorbing unit.
12. Tighten the steering wheel fixing nut to the specified
torque.
Torque: 31 - 39 N




m (3.2 – 4.0 kg




m/23 - 29 lb ft)
13. Support the module and carefully connect the
module connector and horn lead, then install inflato
r
module.
NOTE: Pass the lead wire through the tabs on the
plastic cover (wire protector) of inflator to prevent lead
wire from being pinched.
14. Tighten bolts to specified torque.
Torque: 2 - 4 N




m (0.2 – 0.4 kg




m/17 - 35 lb in)
15. Install driver knee bolster (reinforcement).
16. Install instrument panel lower cover.
17. Install the engine hood opening lever.
18. Connect the yellow 2-way SRS connector and horn
lead located under the steering column.
19. Connect the battery "-" terminal cable. (with SRS ai
r
bag)

TRANSFER CONTROL SYSTEM 7D1-35
3.
Shifting from 4H to 4L
3-1 When the 4L indicator flashes at 2Hz
When shifting from 4H to 4L, the 4L indicator continues flashing at 2Hz until shifting in the transfer case is
completed. The phases of the engaged splines may sometimes deviated preventing completion of shifting.
By correcting the deviation of phases, shifting is completed.

Step 3-1:
(In case of AT): Set the select bar of the transmission to the D position.
(In case of MT): Set the lever of the transmission to a position allowing running and engage the clutch
gently.
At this time, some rotating force acts on the engaged splines, phase is corrected and the engagement is
completed.

3-2 When the 4L indicator flashes at 2Hz for 10 seconds and then keeps ON again (AT vehicle)
This condition occurs when torsional torque has been generated between the transmission and road surface
and the transfer standby mechanism cannot absorb it completely.

Step 3-2:
Set the select lever of the transmission to the N position. (Stepping on the brake pedal is effective at
this time.)

3-3 When the 4L indicator flashes at a frequency of 4Hz
Shifting from 4H to 4L is restricted.
When the vehicle is running, the transmission lever is at the running range and the engine speed is high (L4:
3000rpm or more V6: 2000rpm), the transfer cannot be shifted from 4H to 4L (restriction on operation).

Restriction on operation (Except 4JA1-LT)
The 4H, neutral and 4L shifting mechanism has no synchronization function. Therefore, if relative rotations in the
mechanism become excessive, shifting exerts adverse influence on the internal mechanism of the transfer. To
avoid such a trouble, vehicle condition is detected to restrict the operation (vehicle speed, engine speed and TM
position).
Requirement to restrict the speed: Vehicle should be in stop.
For the reason of the detection logic, time to wait for start of operation may be required.
A/T: If the vehicle is in stop for a long time at the TM running range (D, 1, 2) before operating the AT, waiting
time becomes longer (from 1 second to 3 minutes at the maximum).
M/T: If the vehicle is at stop with the clutch stepped on at the T/M running position (1 – R), the time to wait
becomes longer.
Waiting time means the time commencing from when other requirements (engine speed and T/M position) are
met to permission of the speed restriction. Operation during the waiting time is not permissible.
The waiting time is 1 second at the minimum and increases up to 5 seconds if the above condition continues 3
minutes. After that, the waiting time increases up to 3 minutes in 2 minutes.
When it is clear that the above condition has continued and reduction of waiting time is desirable, turn on or off
the ignition or start and stop the vehicle several meters.
Requirements for permission of restriction on engine speed: Engine speed should be decreased.
The engine speed of 3000rpm (V6: 2000rpm) or below is advisable.
Requirements for permission of restriction on T/M position restriction:
(AT) N range is recommendable
(MT) should be at the neutral.

These requirements for permission should be all met before the switch is operated. If the requirements are met
after operation, operation is not automatically effected but re-operation is required after permission is given.

TRANSFER CONTROL SYSTEM 7D1-37
Step 4-3: (Same procedure as the step 3-3)
Stop the vehicle (close the accelerator and decrease the engine speed to L4: 3000rpm V6: 2000rpm or
below).
(In case of AT): Set the transmission select lever to the N position.
(In case of MT): Set the transmission lever to the neutral position (stepping on the clutch lever is
recommendable).
Push the 4H button.
If the shifting is not completed (indicator flashes at 2Hz), go to the step 4-1.

5. When shifting from 4H or 4L to neutral
(Same procedure is required when shifting from 2H but in such a case, requirements for shifting from
2H to 4H are also applied.)
5-1 Neutral indicator continues flashing at 2Hz
The neutral indicator continues flashing at 2Hz until 4H (4L) is completely separated in the transfer. If
torsional torque has accumulated between the transmission and road surface, separation may be difficult.

Step 5-1:
If the operation is not completed, execute the step 7 for confirmation.
(In case of AT): Set the transmission select lever to the D position.
After confirming that the gears are at the neutral position, return the lever to the N
position.
(In case of MT): Set the transmission lever to a vehicle running position and engage the clutch gently.
After confirming that the gears are at the neutral position, return the lever to the
neutral position

5-2 When the neutral indicator flashes at 4Hz
As in the case of shifting from 4L to 4H, restriction is imposed to the operation from 4L or 4H (including 2H).
If the transmission lever is at a running range and engine speed is high (L4: 3000rpm, V6: 2000rpm or more)
while the vehicle is running, operation from the 4L or 4H (including 2H) of the transfer to the neutral is
impossible (restriction on operation).

Step 5-2:
Stop the vehicle.
(In case of AT): Set the transmission select lever to the N (or P) position.
(In case of MT): Set the transmission lever to the neutral position (at this time, stepping on the clutch
is recommended).
Keep pushing the 2H and 4L button for 10 second.
Follow the start procedure for confirmation. (Confirmation of drive force not transferred; same as in the
step 5-1)
After the confirmation, set the transmission to the neutral position in case of MT or to the neutral
position in case of AT.

7D1-48 TRANSFER CONTROL SYSTEM
From 4H to 4L; Even after the correction step 3-3(*), 4Lo indicator blinks at 4Hz
Step Action Yes No
1 Is the ignition switch ON? Turn it OFF once. Go to step 2.
2 Turn ON the ignition switch and
check the valve. Do not start
the engine.
Has the valve check for 2
seconds been completed
normally? Go to step 3. Refer to the paragraph about the
indicator when it does not react
when shifted from 2H to 4H.
After taking the remedy, trace
this chart from the beginning.
3 Shift to 2H.
Can be shifted to 2H and then to
4H? Go to step 4. Refer to the paragraph about
shifting from 2H to 4H.
In particular, check if not at the
Check4WD condition, return to
this chart and trace it from the
beginning.
4 Set to N position in case of AT
and set to the neutral position in
case of MT and check if the
lamp blinks at 4Hz after
operation.
Failed T/M position switch and
harness (failure of TM1 and TM2
harness and their related
switches shown in the figure).
Incorrect wiring.
Repair as required and trace this
chart from the beginning. Shift back to 4H and go to step 5.
5 Start the engine and travel the
vehicle.
Does the speedometer run at
this time? Go to step 6. Failure of speed sensor or
disconnection or short of harness
(for the meter).
After repairing, trace this chart
from the beginning.
6 Check the harness between the
transfer controller and speed
sensor.
(Check the engine rotation
detection harness at the same
time.)
Is any trouble noticed? Failed harness between the
transfer controller and speed
sensor.
After repairing, trace this chart
from the beginning.
(Repair the engine rotation
detection unit, if required.) Go to step 7.
7 Travel the vehicle several
meters, stop it, meet the
permission requirements for
operation limits.
Did you wait for several seconds
after the requirements were
met? Failed controller.
Replace the controller and trace
this chart from the beginning. You did not wait for enough time.
Optimum waiting time is 1
second or maximum 3 minutes
depending on the previous
conditions.
Refer to the paragraph about
operation without failure.
*Before determining a trouble (Non-trouble mode)

TRANSFER CONTROL SYSTEM 7D1-49
From 4L to 4H: After the correction step 4-3(*), 4Lo indicator blinks at 4H.
Step Action Yes No
1 Is the ignition switch ON? Turn it OFF once. Go to step 2.
2 Turn ON the ignition switch and
check the valve. Do not start
the engine.
Has the valve check for 2
seconds been completed
normally? Go to step 3. Refer to the paragraph about the
indicator when it does not react
when shifted from 2H to 4H.
After taking the remedy, trace
this chart from the beginning.
3 Can be shifted to 2H and then to
4L? Go to step 4.
(Impossible usually.)
Failed controller In case of Check 4WD, shifting to
2H is possible.
Returning to 4L is impossible.
Refer to the paragraph about
Check4WD.
4 Set to N position in case of AT
and set to the neutral position in
case of MT and check if the
lamp blinks at 4Hz after
operation.
Failed T/M position switch and
harness (failure of TM1 and TM2
harness and their related
switches shown in the figure).
Incorrect wiring.
Repair as required and trace this
chart from the beginning. Press the operation switch of 4L
and go to step 5.
5 Start the engine and travel the
vehicle.
Does the speedometer run at
this time? Go to step 6. Failure of speed sensor or
disconnection or short of harness
(for the meter).
After repairing, trace this chart
from the beginning.
6 Check the harness between the
transfer controller and speed
sensor.
(Check the engine rotation
detection harness at the same
time.)
Is any trouble noticed? Failed harness between the
transfer controller and speed
sensor.
After repairing, trace this chart
from the beginning.
(Repair the engine rotation
detection unit, if required.) Go to step 7.
7 Travel the vehicle several
meters, stop it, meet the
permission requirements for
operation limits.
Did you wait for several seconds
after the requirements were
met? Failed transfer controller.
Replace the controller and trace
this chart from the beginning. You did not wait for enough time.
Optimum waiting time is 1
second or maximum 3 minutes
depending on the previous
conditions.
Refer to the paragraph about
operation without failure.
*Before determining a trouble (Non-trouble mode)

7D1-50 TRANSFER CONTROL SYSTEM
To neutral: After the correction step 5-2(*), neutral indicator blinks at 4Hz.
Check the function between H and L according to the chart for 4L to 4H instead of check
for the requirements of neutral.
Step Action Yes No
1 Is the ignition switch ON? Turn it OFF once. Go to step 2.
2 Turn ON the ignition switch and
check the valve. Do not start the
engine.
Has the valve check for 2
seconds been completed
normally? Go to step 3. Refer to the paragraph about the
indicator when it does not react
when shifted from 2H to 4H
(7D1-37).
After taking the remedy, trace
this chart from the beginning.
3 Can be shifted to 2H and then to
4L? Go to step 4.
(Impossible usually.)
Failed controller Refer to the paragraph about
shifting from 2H to 4H.
In particular, check if not at the
Check4WD condition, return to
this chart and trace it from the
beginning.
In case of Check4WD, shifting to
2H is possible.
Returning to 4H is impossible.
Refer to the paragraph about
Check4WD.
4 Set to N position in case of AT
and set to the neutral position in
case of MT and check if the lamp
blinks at 4Hz after operation. Failed T/M position switch and
harness (failure of TM1 and TM2
harness and their related
switches shown in the figure).
Incorrect wiring.
Repair as required and trace this
chart from the beginning. Shift back to 4H and go to step 5.
5 Start the engine and travel the
vehicle.
Does the speedometer run at this
time? Go to step 6. Failure of speed sensor or
disconnection or short of harness
(for the meter).
After repairing, trace this chart
from the beginning.
6 Check the harness between the
transfer controller and speed
sensor.
(Check the engine rotation
detection harness at the same
time.)
Is any trouble noticed? Failed harness between the
transfer controller and speed
sensor.
After repairing, trace this chart
from the beginning.
(Repair the engine rotation
detection unit, if required.) Go to step 7.
7 Travel the vehicle several
meters, stop it, meet the
permission requirements for
operation limits.
Did you wait for several seconds
after the requirements were met? Failed controller.
Replace the controller and trace
this chart from the beginning. You did not wait for enough time.
Optimum waiting time is 1
second or maximum 3 minutes
depending on the previous
conditions.
Refer to the paragraph about
operation without failure.
*Before determining a trouble (Non-trouble mode)
For shifting to neutral, 2H and 4L switches should be kept pressed at the same time for 10 seconds.
For shifting from neutral to other position, 2H, 4H or 4L switch should be kept pressed for 10 seconds.
When shifting from neutral to other position, the lamp blinking at 2Hz indicates active condition.
When the lamp keeps blinking at 2Hz, follow the step for the case when the lamp keeps blinking at 2Hz when
shifting between positions.

7A3-14 ON-VEHICLE SERVICE (AW30 –40LE)

Measure Time Lag
1. Fully apply the parking brake.
2. Start the engine. Check idling speed (A/C OFF).
3. Shift the shift lever from “N" to “D" range. Using a
stopwatch, measure the time it takes from shifting
the lever until the shock is felt.
Time lag: Less than 0.7 seconds
4. In same manner, measure the time lag for “N"


“R".
Time lag: Less than 1.2 seconds
Evaluation
1. If “N" 
“ D" time lag is longer than specified:

Line pressure too low
 Forward clutch malfunction
 No.2 one-way clutch not operating properly
2. If “N" 
“ R" time lag is longer than specified:

Line pressure too low
 Direct clutch malfunction
 No.3 brake malfunction
3. If both time lag is longer than specified:

Line pressure too low

Hydraulic Test



RUW37ALH000201
Preparation

1. Warm up the transmission fluid.
2. Remove the transmission case test plug and mount the hydraulic pressure gauge.
Oil pressure gauge: J –29770 –A
NOTE: Perform the test at normal operation fluid
temperature (50 – 80 
C or 122 – 176 
F).