ISUZU AXIOM 2002 Service Repair Manual

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±92
StepActionYe sNo
11. The car stops, the AT selector is the N position, and the brake
is applied.
When the TOD switch is changed to the TOD (or 2H) position, is
12V observed between terminals 44 and 47 (4L switch)?
Go to Step 2Go to Step 3
21. The car stops, the AT selector is the N position, and the brake
is applied.
When the TOD switch is changed to the 4L position, is 0V
observed between terminals 44 and 47 (4L switch)?
Refer to ªTrouble
intermittently
observedº.
Go to Step 3
31. The car stops, the AT selector is the N position, and the brake
is applied.
2. Select the TOD switch to the TOD (or 2H) position.
Is there the continuity between the connector (C±37) terminal 22
and 25?
Go to Step 5Go to Step 4
41. Connect the ECU connector (C±37) and turn on the starter
switch.
2. The car stops, the AT selector is the N position, and the brake
is applied.
3. Select the TOD switch to the 4L position.
4. Turn off the starter switch and disconnect the ECU connector
(C±37).
Is there the continuity between the connector (C±37) terminal 22
and 25?
The ECU has
failed.Replace
the ECU.
Go to
Step 9Go to Step 5
51. Connect the ECU connector (C±37) and turn on the starter
switch.
2. The car stops, the AT selector is the N position, and the brake
is applied.
3. Select the TOD switch to the TOD (or 2H) position.
4. Turn off the starter switch and disconnect the connector (H±7).
Is there the continuity between the connector terminal (H±7) 5 and
(C±37) 25?
Go to Step 7Go to Step 6
61. Connect the connector (H±7) and turn on the starter switch.
2. The car stops, the AT selector is the N position, and the brake
is applied.
3. Select the TOD switch to the 4L position.
4. After the transfer has changed to the 4L mode, turn off the
starter switch and disconnect the connector (H±7).
Is there the continuity between the connector terminal (H±7) 5 and
(C±37) 25?
Go to Step 7
GND is
short-circuited
between
terminals (C±37)
2 and (H±7) 5.
Repair the circuit.
Go to
Step 9
71. Connect the connector (H±7) and turn on the starter switch.
2. The car stops, the AT selector is the N position, and the brake
is applied.
3. Select the TOD switch to the TOD (or 2H) position.
4. After the transfer has changed to the TOD (or 2H) mode, turn
off the starter switch and disconnect the connector (A±1).
Is there the continuity between the connector terminal (A±1) 12
and GND?
Repair the
transfer.
Go to
Step 9Go to Step 8

4B2±93
DRIVE LINE CONTROL SYSTEM (TOD)
StepNo Ye s Action
81. Connect the connector (A±1) and turn on the starter switch.
2. The car stops, the AT selector is the N position, and the brake
is applied.
3. Select the TOD switch to the 4L position.
4. After the transfer has changed to the 4L mode, disconnect the
connector (A±1).
Is there the continuity between the connector terminal (A±1) 12
and GND?
GND is
short-circuited
between
terminals (A±1)
12 and (H±7) 5.
Repair the circuit.
Go to
Step 9
Repair the
transfer.
Go to
Step 9
9Check that all the parts are mounted.
Is this step complete?
Verify the repair.Go to Step 9

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±94
Chart E±1AXLE switch circuit wires are broken.
Function of circuitÐ
Fail conditionBoth the TOD and 4L modes are disabled. (The transition status is not removed.)
Indicator lamp state
TOD switch positionTOD4L
D04R200023

4B2±95
DRIVE LINE CONTROL SYSTEM (TOD)
StepActionYe sNo
1Start the engine.
When the TOD switch is selected to the TOD position, is 0V
observed between terminals 42 and 47?
Go to Step 2Go to Step 4
21. The car stops, the AT selector is N position, and the brake is
applied.
2. Select the TOD switch to the 4L position.
Is 0V observed between terminals 42 and 47?
Go to Step 3Go to Step 4
31. The car stops, the AT selector is N position, and the brake is
applied.
When the TOD switch is selected to the 4L position, is 12V
observed between the terminal 19 and 47?The phenomenon
is not
reproduced.
Refer to
ªTroubles
intermittently
observedº.
The ECU has
failed.Replace
the ECU.
Go to
Step 8
41. The car stops, the AT selector is N position, and the brake is
applied.
When the TOD switch is selected to the 2H position, is the battery
voltage observed between the terminal 23 and 47.
Go to Step 5Go to Step 7
5When the TOD switch is selected to the TOD position (TOD
mode), is 0 ~ 1V observed between terminals 23 and 47?
Go to Step 6Go to Step 7
61. The car stops, the AT selector is N position, and the brake is
applied.
When the TOD switch is selected to the 4L position, is 0V
observed between terminals 23 and 47?Repair the circuit
or check the
ªFront Axle
Disconnectº.
(Refer to
section
4B
)
Go to
Step 8Go to Step 7
7Is any of the trouble codes 28 (P1760), 32 (P1761) and 33
(P1762) recorded?Examine the
trouble based on
ªDiagnosis from
Trouble Codesº.The ECU has
failed. Replace
the ECU.
Go to
Step 8
8Check that all the parts are mounted.
Is this step complete?
Verify the repair.Go to Step 8

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±96
Chart E±2The AXLE switch circuit is short-circuited to GND.
Function of circuitÐ
Fail conditionEven after the TOD switch is selected to the 2H position, the 2H mode is not enabled.
(The transition status is not removed.)
Indicator lamp state
TOD switch position2H
D04R200023

4B2±97
DRIVE LINE CONTROL SYSTEM (TOD)
StepActionYe sNo
1Start the engine.
When the TOD switch is selected to the TOD position, is 0V
observed between terminals 42 and 47?
Go to Step 2Go to Step 6
21. The car stops, the AT selector is N position, and the brake is
applied.
When the TOD switch is selected to the 4L position, is 0V
observed between terminals 42 and 47?
Go to Step 3Go to Step 6
31. The car stops, the AT selector is N position, and the brake is
applied.
2. Select the TOD switch to the 2H position.
Is 5V observed between terminals 42 and 47?
Go to Step 4Go to Sep 6
4Is 12V observed between terminals 7 and 47?
Go to Step 5
Replace the
ECU.
Go to
Step 10
5Is 12V observed between terminals 19 and 47?The phenomenon
is not
reproduced.
Refer to
ªTroubles
intermittently
observedº.
The ECU has
failed.Replace
the ECU.
Go to
Step 10
61. The car stops, the AT selector is N position, and the brake is
applied.
When the TOD switch is selected to the 2H position, is the battery
voltage observed between terminals 23 and 47?
Go to Step 7Go to Step 9
71. The car stops, the AT selector is N position, and the brake is
applied.
When the TOD switch is selected to the TOD position, is 0V
observed between terminals 23 and 47?
Go to Step 8Go to Step 9
81. The car stops, the AT selector is N position, and the brake is
applied.
When the TOD switch is selected to the 4L position, is 0V
observed between terminals 23 and 47?Repair the circuit
or check the
ªFront Axle
Disconnectº.
(Refer to
section
4B
)
Go to
Step 10Go to Step 9
9Is any of the trouble codes 28 (P1760), 32 (P1761) and 33
(P1762) recorded?Examine the
trouble based on
ªDiagnosis from
Trouble Codesº.The ECU has
failed. Replace
the ECU.
Go to
Step 10
10Check that all the parts are mounted.
Is this step complete?
Verify the repair.Go to Step 10

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±98
Chart GThe trouble codes are displayed.
Function of circuitÐ
Fail condition
Indicator lamp state
TOD switch positionÐ
D04R200009

4B2±99
DRIVE LINE CONTROL SYSTEM (TOD)
StepActionYe sNo
1Disconnect the ECU connector from ECU.
Is there the continuity established between terminals (C±37)7 and
(C±37)25?
Go to Step 2
The ECU has
failed. Replace
the ECU.
Go to
Step 3
2Is the self-diagnostic connector short-circuited?
Go to Step 3
Open the
self-diagnostic
connector.
Go to
Step 3
31. Check that all the parts are mounted.
2. Clear the trouble codes.
Is this step complete?
Verify the repair.Go to Step 3

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±100
Chart HLighting switch circuit
Function of circuitReads in the status of lighting switch, and reduces the indicator at night.
Fail conditionEven if the lighting switch is pressed on and off, brightness does not change.
Indicator lamp state
TOD switch positionAll position (exsample TOD mode)
D04R200009

4B2±101
DRIVE LINE CONTROL SYSTEM (TOD)
StepActionYe sNo
11. Turn on the starter switch.
2. Turn off the lighting switch.
Is 0V observed between the EUC terminal 40 and 47?
Go to Step 2
Lighting switch
battery circuit
short. Repair the
circuit.
Go to
Step 4
2Turn lighting switch ªONº.
Is the battery voltage observed between ECU terminal 40 and 47?
Go to Step 3
Wires are broken
in lighting switch
circuit. Repair the
circuit.
Go to
Step 4
3While the lighting switch is pressed on and off, does the
brightness of the indicator change?The phenomenon
is not
reproduced.
Refer to
ªTroubles
intermittently
observedº
The ECU has
failed. Replace
the ECU.
Go to
Step 4
4Check that all the parts are mounted.
Is this step complete?
Verify the repair.Go to Step 4