2004 ISUZU TF SERIES ignition

TRANSMISSION CONTROL SYSTEM (AW30–40LE) (V6 3.5L) 7A2-61

DTC P0753 (FLASHING CODE 31) Shift Solenoid S1 Electrical



RTW37ALF000601

Circuit Description
The shift solenoi S1 changes the hydraulic route with
the signals from the TCM according to the vehicle
speed and the throttle opening to control shifting. When
the solenoid S1 or S2 fails, the hydraulic circuit is
mechanically operated as a backup.

Condition for setting the DTC
The TCM detects following "Condition 1" and "
Condition 2" for 2 times continuously at shifting.
Condition 1("GND short"):

Voltage at connector pin is 0V for 0.3 sec
continuously when solenoid is “ON".
Condition 2("Open or Ignition short"):

Voltage at connector pin is ignition voltage for 0.5
sec continuously when solenoid is “OFF".

7A2-62 TRANSMISSION CONTROL SYSTEM (AW30–40LE) (V6 3.5L)

Action Taken When The DTC Sets

The TCM operates shifting as following pattern.



Normal Fail S1 S2
1 3 - on
2 3 - on
3 3 - on
4 4 - off

No squat control.
 No engine torque control.

No line pressure control.

No lock-up control.
 No slope control.

Check Trans ON.

DTC stored.

No detect DTC P0722

No detect DTC P0717

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 P0753 (FLASHING CODE 31) Shift Solenoid S1 Electrical


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 P0753? — Go to Step 3 Refer to
Diagnostic Aids
3

1. Key “ON", engine run.

2. Place the selector lever in the "P" range.
3. Measure the voltage between terminal C94-16 and
terminal C94-1 on the TCM pigtail connector by
J39200 DMM.
Is the voltage specified value? 816V Go to Step 4 Go to Step 10

7A2-64 TRANSMISSION CONTROL SYSTEM (AW30–40LE) (V6 3.5L)

DTC P0758 (FLASHING CODE 32) Shift Solenoid S2 Electrical


RTW37ALF000601

Circuit Description
The solenoid S2 changes the hydraulic route with the
signals from the TCM according to the vehicle speed
and the throttle opening to control shifting. When the
solenoid S1 or S2 fails, the hydraulic circuit is
mechanically operated as a backup.

Condition for setting the DTC
The TCM detects following "Condition 1" and "Condition
2" for 2 times continuously at shifting.
Condition 1 ("GND short"):

Voltage at connector pin is 0V for 0.3 sec
continuously when solenoid is “ON".
Condition 2 ("Open or Ignition short"):

Voltage at connector pin is ignition voltage for 0.5
sec continuously when solenoid is “OFF".

TRANSMISSION CONTROL SYSTEM (AW30–40LE) (V6 3.5L) 7A2-65

Action Taken When The DTC Sets
The TCM operates shifting as following patterns.



Normal Fail S1 S2
1 3 - on
2 3 - on
3 3 - on
4 4 - off

No squat control.
 No engine torque control.

No line pressure control.

No lock-up control.
 No slope control.

No torque reduction.

Check Trans ON.

DTC stored.

No detect DTC P0722.

No detect DTC P0717.

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 P0758 (FLASHING CODE 32) Shift Solenoid S2 Electrical


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 P0758? — Go to Step 3 Refer to
Diagnostic Aids
3

1. Key “ON", engine run.

2. Place the selector lever in the "P" range.
3. Measure the voltage between terminal C94-15 and
terminal C94-1 on the TCM pigtail connector by
J39200 DMM.
Is the voltage specified value? 816V Go to Step 4 Go to Step 10

7A2-68 TRANSMISSION CONTROL SYSTEM (AW30–40LE) (V6 3.5L)


 Engine REV is 7000 rpm.

Coolant tempreature is 80

C.

No detect DTC P0712, 0713.
 No detect DTC P0560.
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.

Inspect the wiring for EMI (Erectro-Magnetic
Interference). Check that all wires are properly
routed away from coil, and generator. Also check fo
r
improperly installed electrical options. When this test
is performed, turn “OFF" on electronic autoparts
switches to improperly for a noise preventing.

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.

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) 7A2-75


 No detect DTC P1767.

No detect DTC P0560.

No detect DTC P0712, 0713.
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.

Inspect the wiring for EMI (Erectro-Magnetic
Interference). Check that all wires are properly
routed away from coil, and generator. Also check fo
r
improperly installed electrical options. When this test
is performed, turn “OFF" on electronic auto parts
switches to improperly for a noise preventing.