2004 ISUZU TF SERIES brake

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.

7D1-36 TRANSFER CONTROL SYSTEM
Restriction on operation (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, and TM position).
Requirement to restrict the speed: Vehicle should be in stop.
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:
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.

Note: Don’t’ accelerate engine speed a the time of this operation.

Step 3-3:
Stop the vehicle. (Close the accelerator and decrease the engine speed to below L4: 3000rpm, V6:
2000rpm.)
(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 is
recommendable.) Push the 4L button.
If shifting operation is not completed (the lamp flashes at 2Hz), perform the step 3-1.

4. Shifting from 4L to 4H
4-1 When 4L indicator continues flashing at 2HZ
When shifting from 4L to 4H, the 4L indicator continues flashing at 2Hz until the shifting in the transfer case is
completed. Phases of engaged splines may deviate and the operation may not completed in some cases.
Shifting is completed by correcting the deviation of the splines.

Step 4-1: (same as step 3-1)
(In case of AT): Set the transmission select lever to the D position.
(In case of MT): Shift the transmission lever to a position allowing running and engage the clutch
gently.

4-2 When the indicator continues flashing at 2Hz for 10 seconds and then keeps on at 4L again (AT
vehicle)
This condition occurs when torsional torque has generated between the transmission and the road surface
(use of the parking position on a slope) and resistance against the separation of the driving force cannot be
fully by the waiting mechanism of the transfer.
Shifting is possible by using the brake also at the neutral position of the transmission

Step 4-2: (Same procedure
as the step 3-2)
Set the transmission select lever to the N position.
(Leaving the brake lever and stepping it again is recommendable.)

4-3 When the 4L indicator flashes at 4HZ
Shifting from 4L to 4H is restricted.
When the vehicle is running, transmission lever is at the running range, and the engine speed is high, the
transfer 4L cannot be shifted to 4H.

7A2-2 TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L)

Service Precaution
WARNING: THIS VEHICLE HAS A SUPPLEMENTAL
RESTRAINT SYSTEM (SRS). REFER TO THE SRS
COMPONENT AND WIRING LOCATION VIEW IN
ORDER TO DETERMINE WHETHER YOU ARE
PERFORMING SERVICE ON OR NEAR THE SRS
COMPONENTS OR THE SRS WIRING. WHEN YOU
ARE PERFORMING SERVICE ON OR NEAR THE
SRS COMPONENTS OR THE SRS WIRING, REFE
R
TO THE SRS SERVICE INFORMATION. FAILURE TO
FOLLOW WARNINGS COULD RESULT IN
POSSIBLE AIR BAG DEPLOYMENT, PERSONAL
INJURY, OR OTHERWISE UNNEEDED SRS SYSTEM
REPAIRS.
CAUTION: Always use the correct fastener in the
proper location. When you replace a fastener, use
ONLY the exact part number for that application.
ISUZU will call out those fasteners that require a
replacement after removal. ISUZU will also call out
the fasteners that require thread lockers or thread
sealant. UNLESS OTHERWISE SPECIFIED, do not
use supplemental coatings (Paints, greases, o
r
other corrosion inhibitors) on threaded fasteners or
fastener joint interfaces. Generally, such coatings
adversely affect the fastener torque and the joint
clamping force, and may damage the fastener.
When you install fasteners, use the correct
tightening sequence and specifications. Following
these instructions can help you avoid damage to
parts and systems.
General Description
The AW30-40LE is a 4–speed fully automatic
transmission. It uses a microcomputer as a control unit
to judge running conditions including throttle opening
rate and vehicle speed, then it sets the shifting point in
the optimum timing so that best driving performance
can be achieved.
In addition, the built–in shift mode select function can
select three shift modes according to the driver's
preference:
 Normal mode –Normal shift pattern.
 3rd Start mode –Starts in 3rd gear to reduce
slippage on ice or snow.
 Power mode has a delayed up shift when more
powerful acceleration is required.
Also, the built–in fail–safe function (“backup mode")
assures driving performance even if the vehicle speed
sensor, throttle signal or any solenoid fails.
Further, the self–diagnostic function conducts diagnosis
in a short time when the control system fails, thus
improving serviceability.
The major features of AW30-40LE are as follows:

A compact structure consisting of 2 sets of planetary
gears and flat torque converter.
 Electronic control selects the optimum shift mode according to the driving conditions.
 Electronic control maintains the optimum hydraulic
pressure for clutch, band brake as well as
transmission so that shift feeling is improved.
 Two sets of planetary gears reduce friction of powe
r
train.
Also, a lockup mechanism in the torque converter
reduces fuel consumption.
 Wide gear ratio and high torque rate of torque
converter provide excellent starting performance.

7A2-6 TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L)

TCM Point Table



RTW37ASF000101-1


PIN No. SIGNAL NAME
A1 GND
A2 PRESSURE CONTROL SOLENOID GND
A3 —
A4 PRESSURE CONTROL SOLENOID
A5 L-up SOLENOID
A6 STARTER SW(IG1)
A7 CAN COMMUNICATION (-)
A8 —
A9 —
A10 —
A11 T/M OIL TEMPERATURE SENSOR
A12 T/M OIL TEMPERATURE SENSOR GND
A13 —
A14 —
A15 SHIFT SOLENOID (S2)
A16 SHIFT SOLENOID (S1)
A17 CAN COMMUNICATION (+)
A18 —
A19 —
A20 —
A21 —
A22 —
A23 GND
A24 BATTERY

PIN No. SIGNAL NAME
B1 NEUTRAL START SW (R)
B2 POWER LAMP
B3 CHECK TRANS LAMP
B4 PATTERN SELECT SW (3rd START)
B5 SPEED SENSOR (+)
B6 INPUT REVOLUTION SENSOR (+)
B7 NEUTRAL START SW (D)
B8 NEUTRAL START SW (N)
B9 NEUTRAL START SW (3)
B10 3rd START LAMP
B11 OIL TEMPERATURE WARNING LAMP
B12 DIAGNOSIS TERMINAL
B13 PATTERN SELECT SW (POWER)
B14 SPEED SENSOR (-)
B15 —
B16 INPUT REVOLUTION SENSOR (+)
B17 —
B18 NEUTRAL START SW (L)
B19 NEUTRAL START SW (2)
B20 NEUTRAL START SW (P)
B21 TRANSMISFER LOW 4 SW
B22 BRAKE LAMP SW
B23 DIAGNOSIS OUT PUT
B24 —
B25 —
B26 CRUISE CONTROL UNIT

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

TCM Voltage & Resistance Check Sheet
CHECK ITEM PIN No. VALUE NOTE
VIGN A6 –A1 VIGN
Key “ON ”

A6 –A23 VIGN
Key “ON ”
Backup Power Supply A24 –A1 +B (Always)
Key “ON ”
Inhibitor (Select) SW P B20 –A1 “P ” Range VIGN Key “ON ”

Except “P ” 0V
Inhibitor (Select) SW R B1
–A1 “R ” Range VIGN Key “ON ”

Except “R ” 0V
Inhibitor (Select) SW N B8
–A1 “N ” Range VIGN Key “ON ”

Except “N ” 0V
Inhibitor (Select) SW D B7
–A1 “D ” Range VIGN Key “ON ”

Except “D ” 0V
Inhibitor (Select) SW 2 B19
–A1 “2 ” Range VIGN Key “ON ”

Except “2 ” 0V
Inhibitor (Select)SW 1 B18
–A1 “1 ” Range VIGN Key “ON ”

Except “1 ” 0V
Inhibitor (Select) SW 3 B9
–A1 “3 ” Range VIGN Key “ON ”

Except “3 ” 0V
Power SW B13
–A1 ON 0V Key “ON ”

OFF VIGN
3rd Start SW B4
–A1 ON 0V Key “ON ”

OFF VIGN
Brake SW B22
–A1 ON VIGN Key “ON ”

OFF 0V
AT Oil Temperature
Sensor A11
–A12 20
C 4.6V Engine run.

155

C 1.1V
4L Signal B21
–A1 4L 0V Key “ON ”

2H/4H VIGN
Diag SW B12
–A1 ON VIGN Key “ON ”

OFF 0V
Shift Solenoid A (S1) A16
–A1 P VIGN Engine run.

R VIGN

N VIGN

D –1 VIGN

D –2 VIGN

D –3 0V

D –4 0V

7A2-12 TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L)

Functions of Input / Output Components
Component Function
Transfer low signal Detects the transfer High/Low position.
OD Cancel signal Detects whether the cruise control unit is judged OD cancel mode.
Output revolution sensor
(Transmission) Detects the vehicle speed.
Input revolution sensor
(Transmission) Detects the input revolution (OD direct clutch drum revolution).
Engine revolution sensor Detects the engine revolution with CAN.
Throttle position signal Detects the throttle opening rate with CAN.
Neutral start switch Detects the select lever position.
Pattern select switch Detects whether the driver has selected "NORMAL" or "POWER" mode.
Brake lamp switch Detects whether the driver has pressed the brake pedal or not.
Oil temperature sensor Detects the oil temperature.




I
n
p
u t
Diagnostic start switch Starts self-diagnosis and displays a code for faulty part if any.
I
n
p
u t
/
O
u t
p
u t Data link connector When connected with Tech2 or tester, can communicate the data for function
check, etc.
Shift solenoid S1, S2 Selects shift point and gear position suited to the vehicle running condition on the
basis of TCM output.
Lock-up control solenoid SL Control the lock-up clutch suited to the vehicle running condition on the basis of TCM output.
Pressure control solenoid
STH Adjusts throttle pressure by energizing current of linear pressure control solenoid
to prevent the shift shock and to obtain shift smoothly.
"CHECK TRANS" lamp When trouble has occurred to throttle position sensor, vehicle speed sensor, or
solenoid, "CHECK TRANS" lamp is blinked to warn the driver. If also displays the
trouble code.
A/T OIL TEMP warning
lamp Lights when ATF oil temperature rises. (Turned on at greater than 146


C
(295

F). Turned off at less than 132

C (270

F).
POWER lamp Lights when POWER MODE detected.



O
u
t
p
u
t
3rd Start lamp Lights when 3rd Start MODE detected.
C
o
m
p
u t
e r Transmission Control
Module (TCM) Based on the signal from each switch and sensors, judges necessary shift point
and lock-up operation, and send signal to each solenoid.

7A2-22 TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L)

TRANSMISSION DATA
ITEM UNIT ENGIN RUNNING AT IDLE
Current Gear 1 st/2 nd/3 rd/4 th 1 st
Target Gear 1 st/2 nd/3 rd/4 th 1 st
Vehicle Speed km/h 0 km/h
AT Output Speed (Automatic Transmission) RPM 0 RPM
AT Input Speed (Automatic Transmission) RPM 675725 RPM
Engine Speed RPM 675725 RPM
Throttle Position Sensor Signal % 0.007.00%
AT Oil Temperature (Automatic Transmission) C Depends on conditions
TCM Status Transfer Low /Transfer High Transfer HI
Desired PC Solenoid Pressure (STH) kPa 34.397.0 kPa
Desired PC Solenoid Current (STH) mA 8351020 mA
PC Solenoid Actual Current (STH) mA 8351020 mA
Gear Ratio : 1 Depends on uper hood
TCC Slip Speed RPM 0 RPM
Shift Position Actual P/R/N/L/2/3 P
Inhibitor Switch P/R/N/L/2/3 P
Transmission Check Light On/Off Off
AT Oil Temperature Lamp (Automatic
Transmission) On/Off Off
3 rd Start Lamp On/Off Off
Power Lamp On/Off Off
Shift Solenoid S1 On/Off On
Shift Solenoid S2 On/Off On
Shift Solenoid S3 On/Off Off
Diag Switch Condition On/Off Off
Power Switch On/Off Off
Brake Switch On/Off Off
Cruise Switch On/Off Off
4L Signal On/Off Off
3 rd Start Switch On/Off Off
Coolant Temperature C Depends on conditions
Torque Request (timing Retard) CA 0 CA
Garage Shift Mode On/Off Off
CAN TPS % 0.00%
CAN Signal Valid Counter (ECM)
— 0  255
CAN Signal Valid Counter (TCM) — 0  255

ON-VEHICLE SERVICE (AW30–40LE) 7A3-1
TRANSMISSION
ON-VEHICLE SERVICE (AW30–40LE)
CONTENTS

Service Precaution .................................................
7A3-2
Location of Clutch, Brake, One-Way Clutch
and Solenoid ........................................................
7A3-3
Operation of Clutch, Brake and One-Way
Clutch ....................................................................
7A3-4
Trnasmission Indentification ..............................
7A3-4
Speed Change and Lock-Up Pattern ...............
7A3-5
Overdrive and Lock-Up Operating
Conditions ............................................................
7A3-5
Diagnosis .................................................................
7A3-6
Basic Troubleshooting ........................................
7A3-6
Manual Shifting Test ...........................................
7A3-12
Stall Test ..............................................................
7A3-12
Time Lag Test .....................................................
7A3-13
Hydraulic Test ......................................................
7A3-14
Road Test .............................................................
7A3-15
Shift Pont Chart and Lock-Up Point Chart ..........
7A3-19
Shift Pont Chart ...................................................
7A3-19
Lock-Up Point Chart ...........................................
7A3-20
Transmission Fluid Level and Condition .............
7A3-21
Inspection .............................................................
7A3-21
ATF Replacement ..................................................
7A3-22
Inspection .............................................................
7A3-22
Neutral Start Switch (Mode Switch) .....................
7A3-23
Inspection .............................................................
7A3-23
Removal ...............................................................
7A3-23
Installation ............................................................
7A3-23
Brake Signal ............................................................
7A3-24
Inspection .............................................................
7A3-24
Input and Output Revolution Sensor ....................
7A3-25
Inspection .............................................................
7A3-25
Pattern Select Switch .............................................
7A3-25
Inspection .............................................................
7A3-25
Solenoid ...................................................................
7A3-26
Inspection .............................................................
7A3-26

ATF Temperature Sensor ......................................
7A3-27
Inspection .............................................................
7A3-27
Select Lever ....................................................... 7A3-28 Remove or Disconnect .......................................
7A3-28
Install or Connect .................................................
7A3-29
Shift Cable ......................................................... 7A3-31
Remove or Disconnect .......................................
7A3-31
Install or Connect .................................................
7A3-32
Torque specifications ..........................................
7A3-33
Transmission Control Module (TCM) ...................
7A3-34
Removal ................................................................
7A3-34
Installation .............................................................
7A3-34
Shift Solenoid and Lock-Up Solenoid ...................
7A3-35
Removal ................................................................
7A3-35
Installation .............................................................
7A3-36
Valve Body Assembly and Pressure Control Solenoid .................................................
7A3-37
Removal ................................................................
7A3-37
Installation .............................................................
7A3-39
Rear Oil Seal (Adapter Housing, 4

4) .................
7A3-40
Removal ................................................................
7A3-40
Installation .............................................................
7A3-40
Rear Oil Seal (Extension Housing, 4
2) ..............
7A3-41
Removal ................................................................
7A3-41
Installation .............................................................
7A3-41
Transmission Assembly .........................................
7A3-42
Transmission and Associated Parts .................
7A3-42
Removal ................................................................
7A3-43
Installation .............................................................
7A3-46
Major Components ..............................................
7A3-50