2004 ISUZU TF SERIES Transmission control module

TRANSMISSION CONTROL SYSTEM (AW30–40LE) (V6 3.5L) 7A2-67

DTC P1767 (FLASHING CODE 67) ECM CAN Invalid

RTW37AMF000401

Circuit Description
The automatic transmission control system in AW30-
40LE uses high speed CAN bus system. The individual
CAN bus systems are connected via two interfaces and
can exchange information and data. This allows control
modules that are connected to different CAN bus
systems to communicate. Transmission control
modules in the vehicle that require continuous, rapid
communication are connected to the high speed CAN
bus. The automatic transmission is continuously notified
of the current engine load status. Since the automatic
transmission control module has to react immediately to
load status changes, rapid communication is required
between the engine control module and the automatic
transmission control module. The high speed CAN bus
in the AW30-40LE is designed as a two-wire CAN bus
(twisted pair). The wires are shielded and twisted. The
transmission rate is 500K band.

Condition for setting the DTC
The TCM detects invalid signal for 0.18 sec. (After the
TCM leaves a communication start with the ECM fo
r
0.64 sec)
The TCM detects above condition for 2.0 sec
continuously.
Action Taken When The DTC Sets

The line pressure is max.
 The TCM judges APS(Accelerator Position Sensor)
angle is 0% at the time of shift operation.

No line pressure control.

No engine torque control.
 No lock-up control.

No slope control.

Check Trans ON.

DTC stored.

No squat control.

7A2-70 TRANSMISSION CONTROL SYSTEM (AW30–40LE) (V6 3.5L)

DTC P1790 (FLASHING CODE 61) Transmission Control Module ROM
Checksum Error
Circuit Description
The electrically erasable programable read only
memory (EEPROM) is a permanent memory chip that is
physically solenoid within the TCM. The EEPROM
contans the program and the calibration information
that the TCM needs to control powertrain operation.
Unlike the PROM used in past applications, the
EEPROM is not replace able. If the TCM is replaced,
the new TCM will need to be programmed. Equipment
containing the correct program and calibration for the
vehicle is required to program the TCM.
Condition for setting the DTC
The TCM detects incorrect value of ROM checksum.
Action Taken When The DTC Sets

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.5 (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.

TRANSMISSION CONTROL SYSTEM (AW30–40LE) (V6 3.5L) 7A2-71

DTC P1790 (FLASHING CODE 61) Transmission Control Module ROM
Checksum Error


Step Action Value(s) YES NO
1
Was the Powertrain ON-Board Diagnostic (OBD)
System Check performed? — Go to Step 2 Go to OBD
System Check
2

1. Install the scan tool.

2. Key “OFF" and keep the position for more than 30
seconds.
3. Key “ON".

4. Check the DTC on the scan tool.
Does the scan tool indicate DTC P1791? — Go to Step 3 Refer to
Diagnostic Aids
3 Perform the SPS for the TCM.
Is the action complete? — Go to Step 4 —
4 Recheck the DTC on the scan tool.
Does the scan tool indicate DTC P1790? — Go to Step 5 Verify repair
5 Replace the TCM.
Important:
The replacement TCM must be
programmed (Refer to SPS for procedure).
Is the action complete? — Verify repair —

7A2-72 TRANSMISSION CONTROL SYSTEM (AW30–40LE) (V6 3.5L)

DTC P1791 (FLASHING CODE 62) Transmission Control Module RAM Error
Circuit Description
DTC P1791 is recorded by TCM when there is
malfunction in the RAM.
Condition for setting the DTC
When the TCM can not detect all RAM from following
step in initialize routine.
Step 1: The TCM writes FFh to the RAM .
Step 2: The TCM reads FFh from the RAM.
Step 3: The TCM writes 00h to the RAM.
Step 4: The TCM reads 00h from the RAM.
Action Taken The DTC Sets

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.

TRANSMISSION CONTROL SYSTEM (AW30–40LE) (V6 3.5L) 7A2-73

DTC P1791 (FLASHING CODE 62) Transmission Control Module RAM Error

Step Action Value(s) YES NO
1
Was the Powertrain On-Board Diagnostic (OBD)
System Check performed? — Go to Step 2 Go to OBD
System Check
2

1. Install the scan tool.

2. Key “OFF" and keep the position for more than 30
seconds.
3. Key “ON"

4. Check the DTC on the scan tool.
Does the scan tool indicate DTC P1791? — Go to Step 3 Refer to
Diagnostic Aids
3 Replace the TCM.
Important:
The replacement TCM must be
programmed (Refer to SPS for procedure).
Is the action complete? — Verify repair —

7A2-74 TRANSMISSION CONTROL SYSTEM (AW30–40LE) (V6 3.5L)

DTC U2104 (FLASHING CODE 65) CAN BUSS OFF

RTW37AMF000401

Circuit Description
The automatic transmission control system in AW30-
40LE uses high speed CAN bus system. The individual
CAN bus systems are connected via two interfaces and
can exchange information and data. This allows control
modules that are connected to different CAN bus
systems to communicate. Transmission control
modules in the vehicle that require continuous, rapid
communication are connected to the high speed CAN
bus. The automatic transmission is continuously notified
of the current engine load status. Since the automatic
transmission control module has to react immediately to
load status changes, rapid communication is required
between the engine control module and the automatic
transmission control module. The high speed CAN bus
in the AW30-40LE is designed as a two-wire CAN bus
(twisted pair). The wires are shielded and twisted. The
transmission rate is 500K band.

Condition for setting the DTC
The TCM detects CAN BUS OFF for 0.18 sec (After the
TCM leaves a communucation start with the ECM fo
r
0.64 sec) continously..
Action Taken When The DTC Sets

The throttle pressure is max.

The TCM judges APS(Accelerator Position Sensor)
angle is 0% at the time of shift operation.
 No throttle pressure reduction.

No torque reduction.

No lock-up control.
 No slope control.

No squat control.

Check Trans ON.

DTC stored.

Engine REV is 7000 rpm.
 Coolant tempreature is 80

C.

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

7A3-6 ON-VEHICLE SERVICE (AW30 –40LE)

Diagnosis
Basic Troubleshooting
AW30
–40LE transmission, with Transmission Control
Module (TCM), differs from the Mechanical – Hydraulic
control type transmissions. Accordingly, its
troubleshooting procedure differs also.
Before troubleshooting an TCM, first determine whethe
r
the problem is electrical or mechanical. To do this, just
refer to the basic troubleshooting flowchart provided
below.

If the cause is already known, using the basic
troubleshooting chart below along with the
troubleshooting chart should speed the procedure.




F07R200005-X