2004 ISUZU TF SERIES check engine

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.

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

7A2-8 TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L)

CHECK ITEM PIN No. VALUE NOTE
Shift Solenoid B (S2) A15 –A1 P 0V Engine run.

R 0V Engine run. (Without the
Reverse range lock out)
N 0V Engine run.
D –1 0V

D –2 VIGN

D –3 VIGN

D –4 0V
Lock-up Solenoid A5
–A1 ON VIGN (ex.) It is “ON ” when the
vehicle speed is more than
65km/h.
OFF 0V
Check Trans Lamp B3
–A1 ON 0V Key “ON ”
(The lamp is “ON ” for 3
second after key “ON ”)

OFF VIGN
AT Oil Temperature Lamp B11
–A1 ON 0V Key “ON ”
(The lamp is “ON ” for 3
second after key “ON ”)

OFF VIGN
Power Lamp B2
–A1 ON 0V Key “ON ”
(The lamp is “ON ” when the
Power switch is “ON ”)

OFF VIGN
3 rd Start Lamp B10
–A1 ON 0V Key “ON ”
(The lamp is “ON ” when the
3rd Start switch is “ON ”)

OFF VIGN
AT Oil Temp Sensor
Resistance A11
–A12 20

C
12k
Key “OFF ”

50

C 1.5k

155

C 293

Pressure Control Solenoid
Resistance A4
–A2 About
4 –7

(20

C)
Key “OFF ”
Speed Sensor Resistance B5 –B14 About
560

– 120
(20

C)
Key “OFF ”
Input Revolution Sensor
Resistance B6
–B16 About
560

– 120
(20

C)
Key “OFF ”
Lock-up Solenoid
Resistance A5
–A1 About
10

– 15
(20

C)
Key “OFF ”
Shift Solenoid A (S1)
Resistance A16
–A1 About
10

– 15
(20
C)
Key “OFF ”
Shift Solenoid B (S2)
Resistance A15
–A1 About
10

– 15
(20

C)
Key “OFF ”

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.

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):

7A2-14 TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L)

4. Do you have a DTC?
YES: write down all code numbers and do the DTC
CHECK
NO: the DTC can not help you find the problem.
1. Go through “
CHECK TRANS" CHECK
2. If it is flashing and the flash is 0.4 seconds ON
and 0.4 seconds OFF, this means that you
should have a DTC stored. Please recheck go
to DIAGNOSTIC CHECK
and if you find the
same problem, replace the Powertrain Control
Module (TCM).
Normal




C07RY005-1
Abnormal





C07RY00042-1

“Check Trans" Check

1. Indicator is ON during 3 seconds at ignition but it is
OFF after the engine starts. The indicator is
working normally go to DIAGNOSTIC CHECK
.



RTW37ASH000401
Normal





C07RY005-1

TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L) 7A2-15

2. Indicator is flashing and the flash is 0.4 seconds
ON and 0.4 seconds OFF always when ignition is
on (engine cranked or not). This means that there is
a malfunction. Go to DIAGNOSTIC CHECK
.
Abnormal





C07RY00042-1
3. Indicator is staying ON always when Ignition is ON.
1. This means that connection between the lamp
and the indicator control unit is shorted to
ground.
2. Verify if instrument panel terminal 2 o
f
connector B –23 is shorted to ground.
3. Verify if the indicator control unit connector C –
95 terminal 3 is shorted to ground.
4.
Verify that the instrument panel terminal 30 of
connector B –24 is connected to battery.
5. If problem solved: Go to CHECK TRANS
INDICATOR .
NO: Replace Transmission Control Module
(TCM).
4. Indicator is staying OFF with the ignition ON
(engine OFF).
1. This means that connection between the lamp
and the indicator control unit is shorted to
battery or opened.
2.
Verify if instrument panel terminal 2 of
connector B –23 is shorted to battery or open.
3. Verify if the indicator control unit connector C –
95 terminal 3 is shorted to battery or open.
4.
Verify that the instrument panel terminal 2of
connector B –23 is connected to battery. If not,
check the fuses and the connections (terminal
11 of connector H –6) voltage.