2004 ISUZU TF SERIES lights

ENGINE DRIVEABILITY AND EMISSIONS 6E–205
2 1. Connect the Tech 2.
2. Review and record the failure information.
3. Select “F0: Read DTC Infor By Priority” in “F0:
Diagnostic Trouble Code”.
Is the DTC P0563 stored as “Present Failure”?—Go to Step 3Refer to
Diagnostic Aids
and Go to Step
3
3 1. Using the Tech2, ignition “On” and engine “Off”.
2. Select “Clear DTC Information” with the Tech2 and
clear the DTC information.
3. Operate the vehicle and monitor the “F5: Failed
This Ignition” in “F2: DTC Information”.
Was the DTC P0563 stored in this ignition cycle?—Go to Step 4Refer to
Diagnostic Aids
and Go to Step
4
4 1. Using the Tech 2, ignition “On” and engine “On”.
2. Monitor the “Ignition Voltage” in the data display.
3. Load the electrical system by turning on the
headlights, etc..
Does the Tech 2 indicate correct ignition voltage? Less than 16V Go to Step 5Check the
charging
system and Go
to Step 5
5 Is the battery jamp start cable incorrectly connecting?
—Verify
procedure Go to Step 6
6 Is the ECM programmed with the latest software
release?
If not, download the latest software to the ECM using
the “SPS (Service Programming System)”.
Was the problem solved?—Verify repair Go to Step 7
7 Replace the ECM.
Is the action complete?
IMPORTANT: The replacement ECM must be
programmed. Refer to section of the Service
Programming System (SPS) in this manual.
Following ECM programming, the immobilizer system
(if equipped) must be linked to the ECM. Refer to
section 11 “Immobilizer System-ECM replacement” for
the ECM/Immobilizer linking procedure.—Veri fy repai r— Step A ction Value(s) Yes No

TRANSFER CONTROL SYSTEM 7D1-39
Trouble diagnosis based on the operation switch, transfer indicator lamp and operating
sound “Check 4WD” indicator ON (operation guard based on the transfer actuator
position detection error)
This condition indicates a faulty circuit related with the detection (limit) switches of the system actuator.
Detection (limit) switches detect the actuator operating angle based on their combinations.
The controller monitors transition of the actuator based on the combination of the detection (limit) switch output.
If the transition based on the combinations indicates some trouble, it is memorized, shifting operation is stopped
when the trouble is counted 5 times, and the “Check 4WD” indicator lights up. At this time, the system permits
operation to 2H only.
When such a condition results, inspection of the transfer shift actuator, check of harness related with the
detection (limit) switch, and erasure of the memory of the controller are required.
(Refer to the memory erasure procedure for the erasure of the memory.)
At this time, the position indicator may flash at 4Hz. It means that a detection (limit) switch trouble wad
detected in the operation process shown by that position indicator (example: 4WD indicator when shifting from
2H to 4H).

Caution:
In the course of trouble diagnosis and correction, do not turn ON the ignition with the harness connector of
the transfer actuator disconnected. (Do not disconnect the harness connector of the transfer actuator
when the ignition is ON.)
If the controller is connected at this condition, a limit SW trouble is judged and the above-described
“Check 4WD” condition is brought about.
This can be reset by clearing the memory.
When it is required to disconnect the harness connector of the actuator and turning the ignition ON,
remove the controller at the same time or remove the IG power fuse of the transfer controller.

TRANSFER CONTROL SYSTEM 7D1-41
Diagnosis from symptom
Check4WD lighting up
Step Action Yes No
1 Check what was done before
the trouble occurred.
Was the harness between the
transfer controller and actuator
disconnected with the ignition
kept ON for the purpose of
servicing the vehicle, etc.?
Or, was the ignition turned ON
(power supplied to the transfer
controller) with the harness of
the actuator removed? If the power is supplied with the
actuator not connected, faulty
position detection switch is
considered.
Clear the memory and trace this
chart from the beginning. Go to step 2.
2 Is the ignition switch ON? Go to step 3. Turn the ignition switch ON and
trace this chart from the
beginning.
3 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 4. Indicator lamp burnt out.
Disconnected harness wire .
After repairing, trace this chart
from the beginning.
4 Isn’t the harness between the
Check4WD indicator and
transfer controller GND shorted? GND (body) short of the indicator
harness.
After repairing, trace this chart
from the beginning. Go to step 5.
5 Check the continuity of harness
between the transfer controller
and transfer actuator. Check
the power short and GND short.
Check the GND harness of the
transfer actuator.
Is a trouble noticed? Repair the harness, clear the
memory and trace this chart from
the beginning. Go to step 6.
6 Check the limit switch of the
actuator.
Is a trouble noticed? Failed actuator. Replace the
actuator, clear the memory and
trace this chart from the
beginning. Clear the memory and trace this
chart from the beginning.
Failed controller.
Replace the controller, clear the
memory and trace this chart from
the beginning.
To check the operation after completing the repair and clearing the memory, shift between 2H and 4L 5 times at
least.
To judge the condition more quickly, ask the customer the situation when the Check4WD lamp lighted up.
When the position indicator blinks at a frequency of 4Hz immediately after occurrence of a trouble, position of
failure which the indicator shows may be limited.
(Since it indicates the situation immediately before detection of failure whether the vehicle is running or standstill so
that possibility of failure around that point is high.)
Status of the transfer when the Check4WD lights up is not always the same. Immediately after occurrence of the
failure, 2H can be operated.

TRANSFER CONTROL SYSTEM 7D1-45
Transfer cannot shift to a position other than 4H.
When shifting from 4H to other position, indicator (4WD, 4Lo, Check4WD, neutral) does
not respond (Only 4WD keeps lighting).
Step Action Yes No
1 Is the ignition switch ON? Go to step 2. Failed 4WD indicator and
harness.
After repairing, 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?
Then, only 4H lights up. Go to step 3. Indicator lamps other than the
4WD indicator are burnt out.
(Check for GND short circuit
between the 4WD indicator and
transfer controller.)
Disconnected harness wire.
After repairing, trace this chart
from the beginning.
3 Press the 2H button.
Is the sound of relay heard from
under the seat, and the sound of
running motor heard? Failed controller.
After replacing the controller,
trace this chart from the
beginning. *Failed operation switch. Or
disconnected or shorted of the
harness for the operation switch.
* The operation switch is an analog type switch which reads the internal composite resistance value at the time of
operation. If an abnormal value is detected, it is judged to be an instruction to 4H.

TRANSFER CONTROL SYSTEM 7D1-47
Though the indicator responds when shifting from 4H to 2H(or other position), it returns
to 4H.
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 if the
Check4WD lamp lights up.
Is the Check4WD lamp OFF? Go to step 4. Failed actuator position detection
(limit) switch (LS1, LS2, LS3,
LS4, GND).
Short or disconnection of harness
of this detection switch.
Refer to paragraph of
Check4WD.
After repairing, trace this chart
from the beginning.
4 Press the 2H button.
Is the sound of relay heard from
the transfer controller? Go to step 5. Failed controller.
Replace the controller and trace
this chart from the beginning.
5 Is the sound of running motor
heart? Failed control system of the
transfer mechanism. Check and
repair and trace this chart from
the beginning. Failed actuator motor.
Disconnection of controller motor
drive output circuit or GND short.
After repairing, trace this chart
from the beginning.
If the motor does not or cannot run at all (stuck transfer mechanism, disconnected motor, failed drive circuit), the
lamp blinks at 4Hz when the position is shifted to other position by pressing the button for more 10 seconds (20
seconds in case of neutral position).

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.




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Diagnostic start switch Starts self-diagnosis and displays a code for faulty part if any.
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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.



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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.

7A2-36 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.
DTC P0560 – System Voltage 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 Using a DVM, measure the battery voltage at the
battery.
Is the battery voltage greater than the specified
value? 11.5 V Go to Step 3 Charge battery,
then go to Step
3
3

1. Install a Tech 2.

2. Select “Ignition Volts" on the Tech 2.
3. Start the engine and raise the engine speed to the
specified value.

4. Load the electrical system by turning on the
headlights, high blower, etc.
Is the ignition voltage approximately equal to the
specified value? 2000 RPM
12.8-14.1 VGo to Step 4 Go to
Starting/Chargi
ng
4

1. Ignition “OFF".

2. Disconnect the TCM connector at the TCM.

3. Using a DVM, measure the battery voltage at the
TCM connector C-94.
Is it approximately equal to battery voltage? — Check for
excessive
curren draw
with ignition
“OFF" engine
“OFF". Go to Step 5
5

1. Check for faulty connections at the TCM harness
terminals.

2. Repair as necessary.
Was a repair necessary? — Verify repair Go to Step 6
6 Check for an open battery feed circuit to the TCM.
Is the action complete? — Verify repair Go to Step 7
7 Replace the TCM.
Important:
The replacement TCM must be
programmed. (Refer to SPS for procedure.)
Is the action complete? — Verify repair —

CONSTRUCTION AND FUNCTION 7A1-17

ATF Thermo Sensor

The ATF thermo sensor detects the ATF temperature in the oil pan and sends signal to the TCM.

The ATF thermo sensor is of the thermister type that the resistance value changes according to the ATF
oil temperature.

The lower is the ATF temperature, the larger is the resistance, and vice versa.

When the ATF temperature exceeds 145C, the TCM lights up the ATF temperature warning lamp in the
meter. When the ATF temperature decreases below 128C, the ATF temperature warning lamp goes out.

The ATF thermo sensor is installed to the lower control valve body and integrated with the harness
assembly.













10.0 100.0 1,000.0 10,000.0 100,000.0
-30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160
A TF Temperature (°C)
Resistance (

)

Figure 29. Characteristic of Thermo Sensor


Figure 30. Location of Thermo Sensor
ATF Temperature
(deg. C) Resistance (Ohm)
(Approximately) ATF Temperature
(deg. C) Resistance (Ohm)
(Approximately)
-30 29,614 100 190
-20 16,705 110 149
-10 9,842 120 118
0 6,028 128 98
20 2,500 130 94
40 1,160 135 84
50 819 140 76
60 591 145 68
80 324 150 62