ECO mode ISUZU TF SERIES 2004 Repair Manual

7D1-34 TRANSFER CONTROL SYSTEM

Diagnosis
Before determining a trouble (Non-trouble mode)
1. When shifting from 2H to 4H:
1-1-1 When the flashing frequency of the 4WD indicator is changed from 2Hz to 4Hz (Shft on the fly)
If the load is too large to shift the gears synchronously, the operation is repeated up to 3 times. If the shifting
is not effected after being repeated 3 times, the indicator frequency is changed from 2Hz to 4Hz and, at the
same time, the actuator condition is changed to 2H, indicator flashes at 4Hz for 10 seconds, and then goes
out.
Cause of excessive synchronous shifting load

Extremely low temperature (the oil viscosity of the front differential increases requiring a large load for
synchronization)
 High speed (since the difference of relative revolutions of gears to be shifted synchronously is too large,
required work load per unit time becomes larger).
Step 1-1-1:
Stop the vehicle or decrease the speed and operate as required again.

1-1-2 When the flashing frequency of the 4WD indicator is changed from 2Hz to 4Hz (Rigid and free wheel
Hub) / Block out of meshing spline.
Step 1-1-2:
Run the vehicle forward and backward several meters and operate as required again.

1-2 When the flashing of 4WD indicator at 2Hz continues more than 11.5 seconds (repetition of 3 times of
above No.1 is counted) (Shift on the fly)
If there is difference of revolutions and phases between the front wheel and axle, connecting the front wheel
and axle is difficult.
Until shifting in the transfer and connection of the front wheel and axle are completed

, the indicator flashes
at a frequency of 2Hz. In the above case, the indicator continues flashing at a frequency of 2Hz until the
connection of the front axle is completed. (If the shifting in the transfer is not completed, the flashing
frequency is changed to 4Hz (above No.1).)
By correcting the difference of relative revolutions and deviation of phases, the shifting can be completed.
Step 1-2:
While the vehicle is running, make sure of safety around the vehicle and accelerate or decelerate the
vehicle while going straight.
When the vehicle is at a stop, run the vehicle forward and backward several meters.

2.
When shifting from 4H to 2H
2-1 When 4WD indicator continues flashing at 2Hz
When shifting from 4H to 2H, the 4WD indicator continues flashing at 2Hz until separation in the transfer and
the separation of the front wheel axle are completed
. When torsional torque is accumulated in the drive
system, separation in the transfer and separation of the front axle
is difficult. In such a case, they can be
separated by removing the torsional torque of the drive system.
Step 2-1:
While the vehicle is running, make sure of safety around the vehicle and accelerate or decelerate the
vehicle while going straight.
When the vehicle is in stop, run the vehicle several meters forward and backward.


: Shift on the fly only.

7D1-42 TRANSFER CONTROL SYSTEM
Cannot shift from 2WD to 4H or 4L.

When shifting from 2H to other position, the indicator (4WD, 4Lo, Check4WD, neutral)
does not respond.
Step Action Yes No
1 Is the ignition switch ON? Go to step 2. Turn the ignition switch ON and
trace this chart from the
beginning.
2 Does the transfer-related
indicators (4WD, 4Lo, Check
4WD, neutral) light up for 2
seconds when the ignition
switch is turned ON? Failed operation switch. Only 2H
is stuck at ON condition and 4H-
4L position is internally
disconnected. Or,
Failed controller Indicator lamp burnt out.
Disconnected harness wire .
After repairing, trace this chart
from the beginning.


Even after correction step 1-1(*), 4WD indicator blinks at 4Hz and changes to 2H after 10
seconds.
Step Action Yes No
1 Is the ignition switch ON? Go to step 2. Turn the ignition switch ON and
trace this chart from the
beginning.
2 Does the transfer-related
indicators (4WD, 4Lo, Check
4WD, neutral) light up for 2
seconds when the ignition
switch is turned ON? Go to step 3. Indicator lamp burnt out.
Disconnected harness wire.
After repairing, trace this chart
from the beginning.
3 After 2 seconds, check that the
Check4WD lamp is ON or OFF.
Is the Check4WD lamp OFF? Go to step 4. Failed actuator position detection
switch (LS1, LS2, LS3, LS4,
GND).
Short or disconnection of harness
of this detection switch.
After repairing, trace this chart
from the beginning.
4 Press the 4H button.
Is sound of relay heard from the
transfer control? Go to step 5. Failed controller.
Replace the controller and trace
this chart from the beginning.
5 Is the sound of running motor
heard? Failed control system of the
transfer mechanism. Check and
repair and trace this chart from
the beginning. Failed actuator motor.
Disconnected controller motor
drive output circuit, GND short
circuit. +B fuse blown out.
Disconnection of that harness.
After repairing, trace this chart
from the beginning.
*Before determining a trouble (Non-trouble mode)

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.

7A2-10 TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L)

Control and Functions
Shift Control
The transmission gear is shifted according to the shift
pattern selected by the driver. In shifting gears, the
gear ratio is controlled by the ON/ OFF signal using the
shift solenoid S1 and the shift solenoid S2.
Band Apply Control
The band apply is controlled when in the 3 –2 downshift
(engine overrun prevention) and the garage shift (shock
control).
The band apply solenoid is controlled by the signal from
the Pulse Width Modulation (PWM) to regulate the flow
of the oil.
Torque Converter Clutch Control
The clutch ON/OFF is controlled by moving the
converter clutch valve through shifting Torque
Converter Clutch (TCC) solenoid using the ON/OFF
signal.
Line Pressure Control
The throttle signal allows the current signal to be sent
to the force motor. After receiving the current signal,
the force motor activates the pressure regulator valve
to regulate the line pressure.
On –Board Diagnostic System
Several malfunction displays can be stored in the
Transmission Control Module (TCM) memory, and read
out of it afterward.
The serial data lines, which are required for the testing
of the final assembly and the coupling to othe
r
electronic modules, can be regulated by this function.
Fail –Safe Mechanism
If there is a problem in the transmission system, the
TCM will go into a “backup" mode.
The vehicle can still be driven, but the driver must use
the select lever to shift gears.
Torque Management Control
The transmission control side sends the absolute spark
advance signal to the engine control side while the
transmission is being shifted. This controls the engine
spark timing in compliance with the vehicle running
condition to reduce the shocks caused by the change o
f
speed.
ATF Warning Control
The oil temperature sensor detects the ATF oil
temperature to control the oil temperature warning,
TCC, and the 3rd start mode.
Reverse Lock Out Control
With the selector lever in reverse position, the TCM will
not close the PWM solenoid until the vehicle is below
15 km/h (9.3 mph), thus preventing reverse
engagement above this speed.

Downhill Control
This mode is automatically activated from NORMAL
mode only when downhill conditions are recognized.
The shift pattern is identical to NORMAL mode except
3-4 and 4-3 shift lines at low throttle modified to get
engine braking on a larger speed range.
Uphill Control
When uphill condition are recognized the 2-3 and 3-4
shift and TCC apply are down only when the engine
torque is sufficient in order to avoid shift hunting.
Gear Shift Control 3rd start


SELECT LEVER RANGE SHIFT PATTERN
D(Drive) 1


2TCC

3TCC

4TCC
3(Third) 1

2TCC

3TCC
2(Second) 1

2(
3)
L(First) 1(
2)
TCC: Torque Converter Clutch
(Notice1): “( )" means over-revving prevention control.
Mode Type


Mode Type Select lever position
Normal drive mode
(NOR) Entire range (excluding “R")
Power drive mode
(PWR) Entire range (excluding “R")

Mode Selection



SWITCH(SW) LAMP
Mode Type PWR/N
OR.S 3RD
START SW POWER
DRIVE LAMP 3RD
START LAMP
Normal
drive mode
(NOR) OFF OFF OFF OFF
Power
drive mod
(PWR) ON OFF ON OFF
3rd Start
mode OFF ON OFF ON
However, the 3rd start switch prevails over the
PWR/NOR switch.
The mode become normal drive mode when the 3rd
start switch is operated from ON to OFF.

TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L) 7A2-11

Comparison of mode
1. The normal drive mode is set at the normal shift
points.
2. The shift points of the power drive mode are shifted
to the higher speed side, compared to the normal
drive mode.
3. The 3rd start mode is a special mode used
exclusively for starting in third gear.
3rd start Mode
1. The 3rd start switch will operate when switched on
after all of the following conditions are present:
a. The gear select position is “D" range only.
b. Vehicle speed is 11 km/h (7 mph) or less.
c. Transmission oil temperature is 120

C (248

F)
or less.
d. Accelerator opening is at 8% or less.
2. Cancel Release
1. Cancellation by driver
a. Turning off the 3rd start mode switch
b. Shifting select position to “3", “2", or “L" (3rd
start mode is not canceled by selecting “N",
“ R", or “P")
c. Ignition key is turned off.
2. Automatic cancellation
a. When vehicle runs at 34 km/h (21mph) o
r
more for 1 second or more
b. When transmission oil temperature reaches 120

C (284

F) or above
NOTE: The mode returns to normal drive mode o
r
power drive mode after the 3rd start mode is canceled.
Backup Mode
If a major system failure occurs which could affect
safety or damage the transmission under normal
vehicle operation, the diagnostic system detects the
fault and overrides the Transmission Control Module
(TCM).
The “CHECK TRANS" light flashes to alert the driver,
and the transmission must be manually shifted as
follows:


Select lever position Gear Ratio Selected
D 4 (Fourth)
Manual 3 4 (Fourth)
Manual 2 3 (Third)
Manual L 3 (Third)
R Reverse
Shifts are firmer to prevent clutch slip and consequent
wear. The fault should be corrected as soon as
possible.

TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L) 7A2-21

Diagnostic Trouble Codes
The purpose of the “Diagnostic Trouble Codes" mode is
to display stored TCM trouble codes.
When “Diagnostic Trouble Codes" is selected an
“ Application Menu" screen appears.
Clear DTC Information
The purpose of the “Clear DTC Information" mode is to
command the clearing of stored TCM trouble codes.
When “Clear DTC Information" is selected, a “Clea
r
DTC Information", warning screen appears. This screen
informs you that by cleaning DTC's, “all stored DTC
information in controller will be erased".
Do you want to clear DTC's (Yes/No).
Press either the Yes or No key when answering.
After clearing codes, confirm system operation by test
driving the vehicle.
Allow the vehicle to shift through all four forward gears
in a manner which attempts to repeat the failure
condition.
NOTE: When the trouble has not been repaired and
the trouble code cannot be erased, check the vehicle
again.
DTC Information
When “DTC Information" is selected, an “Application
Menu" appears with a list of DTC information function
keys addressing DTC specifics and their origins.
Function key selections may vary for particular vehicle
and/or system.
Data Display
The purpose of the “Data Display" mode is to
continuously monitor data parameters.
The current actual values of all important sensors and
signals in the system are display through F1 mode.
When “Data Display" is selected an “Application Menu"
appears. Please select either “Engine" or “Transmission
Data Display".
See “Transmission Data" on next page.
Snapshot
When “Snapshot" is selected an “Application Menu"
appears.
When “Transmission Snapshot" application is selected
from the “Application Menu", a “Snapshot Menu"
appears, displaying several options. “Snapshot" options
may vary from one system to another.
“ Snapshot" allows a recording of all vehicle parameters.
There parameters may then be replayed at a future
point in time.
This action allows you to focus on making the condition
occur, rather than trying to view all of the data in
anticipation of the fault. The snapshot will collect
parameter information around a trigger point that you
select.

When a snapshot is taken. It is recorded onto the
PCMCIA memory card. When the Tech 2 is powered
down. Snapshots are not lost.
Actuator Tests
The purpose of “Actuator Tests" mode is to check fo
r
correct operation of electronic system actuators.
Lamps
You can operate the lamps by pressing the “ON" and
“ OFF" buttons.
Preconditions: none
Solenoid
Solenoid A(S1), Solenoid B(S2)
You can operate the solenoids by pressing the “ON"
and “OFF" buttons.
Preconditions: P –N position, no vehicle speed, no
engine speed
Pressure Control Solenoid (PCS)
You can set desired PCS Current using the “ON" (+20)
and “OFF" (-20) button. The PC Solenoid Data informs
about PCS Current, Pressure and Duty Cycle.
Preconditions: P –N position, no engine speed, no
vehicle speed
NOTE: Freeze Frame
Freeze Frame is an element of the Diagnostic
Management System which stores various vehicle
information at the moment an emission-related fault
is stored in memory and when the Check Transe
Lamp is commanded on. These data can help to
identity the cause of a fault. Refer to Storing An
d
Erasing Freeze Frame Data for more detaile
d
information.

7A2-40 TRANSMISSION CONTROL SYSTEM (AW30–40LE) (V6 3.5L)

Condition 2 ("Short"):
When the TCM detects 2 times or more signals o
f
range sensor more than 0.025 sec at following
conditions.

Vehicle speed is more than 19 mph.
 Engine speed is more than 1500 rpm.
Action Taken When The DTC Sets

No 3rd start mode.
 No slope control.

The TCM judges always D range position of range
sensor at "Condition 1".

The TCM judges the position of range sensor with
following priority at "Condition 2".

There is a priority in order of D, 3, 2, L, R, N, and P.

Check Trans ON.

DTC stored.
Conditions For Clearing The DTC

The DTC can be cleared from the TCM history by
using a scan tool.
 The DTC will be cleared from history when the
vehicle has achieved 40 warm-up cycles without a
failure reported.

After more than 1 second has elapsed after the
ignition key has been turned “ON", short between
No.11 and No.4 (ground) of DLC (Data Link
Connector). Then, after 1 second, but within 6
seconds, discontinue shorting.

Diagnostic Aids

Inspect the wiring for poor electrical connection at
the TCM. Look for possible bent, backed out,
deformed or damaged terminals. Check for weak
terminal tension as well. Also check for a chafed wire
that could short to bare metal or other wiring.
Inspect for a broken wire inside the insulation.

When diagnosing for a possible intermittent short o
r
open condition, move the wiring harness while
observing test equipment for a change.
 Check range sensor for proper mounting and
adjustment.

7A4–128 UNIT REPAIR (AW30–40LE)
Main Data and Specifications
General Specifications
Remaks
Model AW30–40LE
Engine 6VE1 (3.5L)
Type Electronic control planetary gear type
3–element 1–stage 2–phase type
(with lock-up mechanism)
Gear ratio 1st 2.804
2nd 1.532
3rd 1.000
4th (O/D) 0.705
Reverse 2.394
Oil used Name BESCO ATF III
Q'ty (l) 8.7
Torque converter 2100  150 Stall speed (rpm)
Friction element
Forward clutch C–15
Number of discs Direct clutch C–24
OD direct clutch C–02
Second coast brake B–1 40 mm Band width or
Number of discs
Second brake B–25
Number of discs First and reverse brake B–36
Overdrive brake B–04
Clutch
One-way clutch No.1 F–122
Number of
sprage One-way clutch No.2 F–228
OD one-way clutch F–024
Planetary gear
Front planetary Sun gear 42
Number of teeth Pinion gear 19
Ring gear 79
Rear planetary Sun gear 33
Pinion gear 23
Ring gear 79
O/D planetary Sun gear 33
Pinion gear 23
Ring gear 79