section 8 ISUZU TF SERIES 2004 Workshop Manual

TRANSFER CONTROL SYSTEM 7D1-1
SECTION 7D1
TRANSFER CONTROL SYSTEM
TABLE OF CONTENTS
PAGE
Service Precaution .................................................................................................... 7D1 - 2
General Description ................................................................................................... 7D1 - 3
System Components ................................................................................................. 7D1 - 5
Parts Location ...................................................................................................... 7D1 - 5
Functions of Switch and Indicator Lamp ................................................................. 7D1 - 11
Parts Location ............................................................................................................ 7D1 - 23
Circuit Diagram .......................................................................................................... 7D1 - 27
Connector List ........................................................................................................... 7D1 - 31
Diagnosis .................................................................................................................... 7D1 - 34
Before determining trouble ................................................................................. 7D1 - 34
Memory erasing procedure ....................................................................................... 7D1 - 40
Diagnosis from symptom .......................................................................................... 7D1 - 41

WORKSHOP MANUAL
TF SERIES
TRANSMISSION
AW30-40LE MODEL
SECTION 7A

TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L) 7A2-13

CAN bus systems in automatic
transmission control (AW30-40LE)
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.
High speed CAN bus
Transmission control modules in the vehicle that require
continuous, rapid communication are connected to the
high speed CAN bus. For example, 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 transfer rate is
500 K baud.




RUW37ASF000401
Diagnosis
Electronic Diagnosis
How To Diagnose The Problem
1. To avoid incorrect diagnostics, this book needs to
be followed accurately. Unless stated, do not jump
directly to a section that could contain the
solution. Some important information may be
missed.
2. The sections in CAPITALS and bold are the main
sections that can be found in the contents.
3. The go to “
SECTION"
means to continue to check
going to the “section".
4. The go through “
SECTION"
means to go through
the “section" and then to go back to the place the
go through was written.
5. BASIC ELECTRIC CIRCUITS:
You should understand the basic theory o
f
electricity. This includes the meaning of voltage,
amps, ohms, and what happens in a circuit with an
open or shorted wire. You should also be able to
read and understand wiring diagrams.
Check Trans Indicator
Find CHECK TRANS indicator and verify if it is
A. Flashing: Go to DIAGNOSTIC CHECK.
B. Staying on: Go through CHECK TRANS CHECK
.
C. Is never ON when the ignition key is turned on: Go through CHECK TRANS CHECK
D. Is ON during 3 seconds at ignition but OFF after: Normal operation. No DTC or malfunction.



RTW37ASH000401
On Board Diagnostic Check
This test determines if the transmission or its input or
output connections or sensors are failing.
1. Connect the Tech 2: Go through Tech 2 OBD
CONNECTION .
2. Turn on the ignition but not the engine.
3. Push “F0" on Tech 2 to see the Diagnostic Trouble
Code (DTC):

7A2-32 TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L)

Clear DTC
NOTE: If you clear the DTC (Diagnostic Trouble
Codes) you will not be able to read any codes recorded
during the last occurrence.
NOTE: To use the DTC again to identify a problem,
you will need to reproduce the fault or the problem.
This may require a new test drive or just turning the
ignition on (this depends on the nature of the fault).
1. IF you have a Tech 2:
1. Connect the Tech 2 if it is still not connected go
through Tech 2 OBD CONNECTION.
2. Push “F1: Clear DTC Information" in the
Application Menu and answer “Yes" to the
question “Do you want to clear DTC's?"
a. When a malfunction still exists and the Tech 2 displays “AW30-40 CODES NOT
CLEARED". This means that the problem is
still there or that the recovery was not done.
Please go to DTC CHECK.
b. When a malfunction has been repaired and the recovery is done the Tech 2 displays
“ AW30-40LE CODES CLEARED".
2. When you have no Tech 2, the storaged trouble
codes can be cleared by shorting the terminals
No.11 and No.4 or 5 (ground) of data link connecto
r
with a lead wire for 1  6 seconds.
DTC Check
1. Diagnostic Trouble Codes (DTC) have been
identified by Tech 2.
2. You have written the list of the DTCs. The order o
f
the malfunctions has no meanings for this TCM.
Usually only one or two malfunctions should be set
for a given problem.
3. Check directly the DTCs you identified. The DTCs
are sorted by number. Refer to Diagnostic Trouble
Code (DTC) Identification in this section.
TCM Precaution
The TCM can be damaged by:
1. The electrostatic discharge
2. The short circuit of some terminals to voltage or to
ground.
Electrostatic Discharge Damage Description: 1. Electronic components used to control systems are often designed to carry very low voltage, and
are very susceptible to damage caused by
electrostatic discharge. It is possible for less than
100 volts of static electricity to cause damage to
some electronic components. By comparison, it
takes as much as 4,000 volts for a person to even
feel the zap of a static discharge.
2. There are several ways for a person to become
statically charged. The most common methods o
f
charging are by friction and induction. An example
of charging by friction is a person sliding across a
car seat, in which a charge of as much as 25,000
volts can build up. Charging by induction occurs
when a person with well insulated shoes stands
near a highly charged object and momentarily
touches ground. Charges for the same polarity are
drained off, leaving the person highly charged with
the opposite polarity. Static charges of either type
can cause damage, therefore, it is important to
use care when handling and testing electronic
components.
NOTE: To prevent possible electrostatic discharge
damage:
1. Do not touch the TCM connector pins or soldered
components on the TCM circuit board.
2. Be sure to follow the guidelines listed below i
f
servicing any of these electronic components:
3. Do not open the replacement part package until it is time to install the part.
4. Avoid touching electrical terminals of the part.
5. Before removing the part from its package, ground
the package to a known good ground on the
vehicle.
6.
Always touch a known good ground before handling
the part. This step should be repeated before
installing the part if the part has been handled
while sliding across the seat, while sitting down
from a standing position or while walking some
distance.
Information On TCM
1. The Transmission Control Module (TCM) is located
in the place of a clutch pedal and is the control
center of the electronic transmission control
system.
2. The TCM must be maintained at a temperature below 85

C (185

F) at all times. This is most
essential if the vehicle is put through a paint baking
process. The TCM will become inoperative if its
temperature exceeds 85

C (185

F). Therefore, it is
recommended that the TCM be removed or that
temporary insulation be placed around the TCM
during the time the vehicle is in a paint oven o
r
other high temperature process.
3. The TCM is designed to process the various inputs and then respond by sending the appropriate
electrical signals to control transmission upshift,
downshift, shift feel and torque converter clutch
engagement.
4. The TCM constantly interprets information from the
various sensors, and controls the systems that
affect transmission and vehicle performance. By
analyzing operational problems, the TCM is able to

7A2-44 TRANSMISSION CONTROL SYSTEM (AW30–40LE) (V6 3.5L)

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 oil temperature sensor for proper mounting
and adjustment.



DTC P0712 (FLASHING CODE 15) Transmission Oil Temperature Sensor
Circuit Low Input


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 Perform the transmission fluid checking procedure.
Refer to checking Transmission Fluid level and
Condition in Automatic Transmission 7A section.
Was the fluid checking procedure performed ? — Go to Step 3 Refer to
Checking
Transmission
Fluid level and
Condition in
Automatic
Transmission
(AW30-40LE)
section
3

1. Install the scan tool.

2. Key “ON"
3. Review and record scan tool data.

4. Operate the vehicle with in scan tool data.
Does the scan tool indicate DTC P0712 ? — Go to Step 4 Refer to
Diagnostic Aids
4 Measure the voltage of the transmission fluid
temperature sensor by the J39200 DMM.

1. Key “OFF".
2. Disconnect the oil temperature sensor connector.

3. Key “ON".

4. Connect the J39200 DMM to the each terminal of
the oil temperature sensor connector E83-2 and
E83-1.
Does the scan tool indicate less than specified
value ? 5V Go to Step 5 Go to Step 6
5 Replace the transmission fluid temperature sensor.
Is the action complete ? — Verify repair —

TRANSMISSION CONTROL SYSTEM (AW30–40LE) (V6 3.5L) 7A2-47

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 oil temperature sensor for proper mounting
and adjustment.

DTC P0713 (FLASHING CODE 16) Transmission Oil Temperature Sensor
Circuit Hight Input


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 Perform the transmission fluid checking procedure.
Refer to Checking Transmission Fluid Level and
condition Automatic Transmission7A section.
Was the fluid checking procedure performed ? — Go to Step 3 Refer to
checking
Transmission
Fluid Level and
Condition
Automatic
Transmission
(AW30-40LE)
section
3

1. Install the scan tool ?

2. Key “ON"
3. Review and record scan tool date.

4. Operate the vehicle with in scan tool data.
Does the scan tool indicator DTC P0713 ? — Go to Step 4 Go to
Diagnostic Aids
4 Observe the voltage of the transmission fluid
temperature sensor on the TECH2 data.

1. Key “OFF".

2. Disconnect the transmission fluid temperature
sensor connector E-83
3. Install a fused jumper wire from terminal E83-2 to
E83-1 on the mission harness.

4. Key “ON".
Does the scan tool indicate more than specified
value ? 0.4V Go to Step 5 Go to Step 6
5 Replace the transmission fluid temperature sensor .
If the action complete ? — Verify repair —

TRANSMISSION CONTROL SYSTEM (AW30–40LE) (V6 3.5L) 7A2-59


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.


DTC P0748 (FLASHING CODE 35) Pressure Control Solenoid Malfunction


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 “ON".
3. Review and record scan tool data.

4. Operate the vehicle within scan tool data.
Does the scan tool indicate DTC P0748? — Go to Step 3 Refer to
Diagnostic Aids
3 Perform the transmission fluid checking procedure.
Refer to checking Transmission Fluid level and
Condition in Automatic Transmission 7A section.
Was the fluid checking procedure performed? — Go to Step 4 Refer to
checking
Transmission
Fluid level and
Condition in
Automatic
Transmission
(AW30-40LE)
section

7A3-16 ON-VEHICLE SERVICE (AW30 –40LE)

Evaluation
i. If there is no 1 
2 upshift:

Solenoid S2 is stuck
 1 –2 shift valve is stuck
ii. If there is no 2 
3 upshift:

Solenoid S1 is stuck
 2 –3 shift valve is stuck
iii. If there is no 3 
OD upshift (throttle valve opening
1/2):

Solenoid S2 is stuck
 3 –OD shift valve is stuck
iv. If the shift point is defective: Refer to TROUBLESHOOTING CHART in this
section.
v. If the lock-up is defective: Refer to TROUBLESHOOTING CHART in this
section.
2. In the same manner, check the shock and slip at the 1 
2, 2 
3 and 3 
OD upshifts.
NOTE: Drive the vehicle on level ground.
Evaluation
If the shock is excessive:
Refer to TROUBLESHOOTING CHART in this section.
3. Run at “D" range lock-up or OD gear and check fo
r
abnormal noise and vibration.
NOTE: The check for the cause of abnormal noise and
vibration must be made with extreme care as it could
also be due to loss of balance in the propeller shaft,
differential, the torque converter, etc. or insufficient
bending, rigidity, etc. in the power train.



RUW37ASH000201

4. While running in “D" range, 2nd, 3rd gears and OD,
check to see that the possible kick-down vehicle
speed limits for 2 1, 3 1, 3 2, OD 3 and
OD 
2 kick-downs conform to those indicated on
the automatic shift diagram.



RUW37AMH000101
5. Check for abnormal shock and slip at kick-down.
6. While running in “D" range, OD gear or “lock-up",
shift to “2" and “L" ranges and check the engine
braking effect at each of these ranges.
7. Also check to see that downshift is made from 3 
2
or from OD to 3 and then to 2 immediately and that
2 
1 downshift point is within the limits shown in the
diagram when tested by releasing the accelerato
r
pedal and shifting into position of “L" while driving in
the third gear or in overdrive.

ON-VEHICLE SERVICE (AW30 –40LE) 7A3-35

Shift Solenoid and Lock-Up Solenoid
Removal
Preparation:

Disconnect negative ( –) battery cable.
 Drain the fluid.
Refer to ATF REPLACEMENT in this section.
1. Remove oil lever gage and oil filler tube.
2. Support transfer case (4
4) or rear cover (42)
with a transmission jack.
3. Remove engine rear mounting nuts.


F07RW008
4. Remove fule pipe heat protector on tansmission
corssmenber.
5. Remove fuel pipe from the crossmenber.
6. Remove transmission crossmenber.
7. Remove the nineteen bolts.
8. Remove oil pan, using seal cutter J –37228.



RUW37ASH002901

NOTE: Do not turn over the transmission as this will
contaminate the valve body with foreign materials in the
bottom of the oil pan.
Remove oil pan by lifting the transmission case.
Oil pan seal cutter: J –37228
Examine particles in oil pan
Remove the magnet and use it to collect any steel
chips.
Look carefully at the chips and particles in the oil
pan and on the magnet to anticipate what type o
f
wear you will find in the transmission:
Steel (magnetic) ..................bearing, gear and
clutch plate wear
Brass (non-magnetic) ..........bushing wear



240RY00008
9. Remove the oil strainer assembly.



244RY00003

7A3-36 ON-VEHICLE SERVICE (AW30 –40LE)

10.Disconnect the solenoid wiring connectors from the
shift solenoid S1(1), S2(2), lock-up solenoid(3) and
pressure control solenoid(4).



249RY 00011



249RY 00012
11. Remove each retaining bolts and solenoids. (Except
pressure control solenoid:)
Pressure control solenoid cannot be removed.
Installation
To install, follow the removal steps in reverse order
noting the following point;
Refer to the section Reassembly of Majo
r
Components(2) and Transmission Removal an
d
Installation .
Torque:
Solenoid S1, S2 bolt – 7 N m (61 Ib in)
Lock-up solenoid bolt – 10 N m (87 Ib in)