ISUZU TROOPER 1998 Service Repair Manual

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±50
Check flowTrouble codePhenomenonStandard
1128The shift on the fly system (front
hub) works incorrectly.Ð
NOTE: T h e s h i f t o n t h e f l y s y s t e m i s n o t changed
between 2WD and 4WD modes normally.CAUTION: If code 32 or 33 is also observed, remove
the trouble associated with code 32 or 33 first.
D04RW058

4B2±51 DRIVE LINE CONTROL SYSTEM (TOD)
StepActionYe sNo
11. Turn on the starter switch.
2. Set the transfer to the 2H mode.
Is the battery voltage observed between terminals 5 and 19?
Go to Step 2Go to Step 5
2Is the battery voltage observed between terminals 10 and 19?Go to Step 3Go to Step 6
31. Set the transfer to the high (TOD) mode.
Does the voltage between terminals 5 and 19 indicate 0V?
Go to Step 4
The ECU has
failed. Replace
the ECU.
Go to Step 7
4Does the voltage between terminals 10 and 19 indicate 0V?The phenomenon
is not
reproduced.
Refer to
ªTroubles
intermittently
observedº.
Go to Step 7
The shift on the
fly system is
failed (refer to
Section 4C ªFront
Axleº of Chassis
Repair Manual).
Go to Step 7
5Does the TOD indicator show the 2H mode?
The ECU has
failed. Replace
the ECU.
Go to Step 7
See ªTrouble
Diagnosis
Depending on
The Status of
TOD Indicatorº.
Go to Step 7
6Set the transfer to the high (TOD) mode.
Does the voltage between terminals 5 and 19 indicate 0V?The shift on the
fly system has
failed (refer to
Section 4C ªFront
Axleº of Chassis
Repair Manual).
Go to Step 7
The ECU has
failed. Replace
the ECU.
Go to Step 7
71. Check that all the parts are mounted.
2. Clear the trouble code.
Is this step complete?
Repeat the
ªDiagnosis Flowº.
Return to Step 7

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±52
Check flowTrouble codePhenomenonStandard
1232The on/off signal (ADC) line of the
shift on the fly system (front hub) is
broken, or the line is short-circuited
to the battery.
Ð
NOTE: The on/off signal line of the shift on the fly system
is broken, or the line is short±circuited to the battery.
D04RW058

4B2±53 DRIVE LINE CONTROL SYSTEM (TOD)
StepActionYe sNo
11. Turn off the starter switch.
2. Disconnect the ECU connector from ECU.
Is the continuity established between terminals (B±67)5 and
(B±67)11?
Go to Step 2
The harness is
broken. Repair
the circuit.
Go to Step 3
2Does the voltage between terminals 5 and 19 indicate 0V?
Go to Step 3
The battery is
short-circuited.
Repair the circuit.
Go to Step 4
31. Turn off the starter switch.
2. Connect ECU connector.
3. Turn on the starter switch.
4. Set the transfer to the 2H mode.
Is the battery voltage observed between terminals 5 and 19?The phenomenon
is not reproduced
Refer to
ªTroubles
intermittently
observedº.
Go to Step 4
The ECU has
failed. Replace
the ECU.
Go to Step 4
41. Check that all the parts are mounted.
2. Clear the trouble code.
Is this step complete?
Repeat the
ªDiagnosis Flowº.
Return to Step 4

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±54
Check flowTrouble codePhenomenonStandard
1333The ADC line is short-circuited to
GND.Ð
NOTE:

The on/off signal line of the shift on the fly system is
short±circuited to GND.
The system enters into the fail-safe mode because of
fusing or system protection.
(If a short±circuit is observed on GND, the output to
the on/off signal line becomes 0V.)
D04RW059

4B2±55 DRIVE LINE CONTROL SYSTEM (TOD)
StepActionYe sNo
11. Turn off the starter switch.
2. Disconnect the ECU connector from ECU.
Does the resistance between terminals 5 and 19 meet the
standard, R = 21 + 4 ohms?The phenomenon
is not
reproduced.
Refer to
ªTroubles
intermittently
observedº.
Go to Step 4
Go to Step 2
2Is the resistance between terminals 5 and 19 R<2 ohms?The signal line
circuit of the shift
on the fly system
is short-circuited
to GND. Repair
the circuit.
Go to Step 3
Go to Step 3
3Is the resistance between terminals 5 and 19 R= 9+7ohms?The signal line
circuit of the shift
on the fly system
is layer
short-circuited*.
Replace the valve
(VSV).
Go to Step 3
Go to Step 4
41. Check that all the parts are mounted.
2. Clear the trouble code.
Is this step complete?
Repeat the
ªDiagnosis Flowº.
Return to Step 4
*Layer short-circuit : The coil is damaged by overcurrent.

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±56
Check flowTrouble codePhenomenonStandard
1425The CHECK lamp indicator line is
short±circuited to the battery.Ð
35The line is broken or short±circuited
to GND.Ð
D04RW058

4B2±57 DRIVE LINE CONTROL SYSTEM (TOD)
StepActionYe sNo
11. Turn on the starter switch.
Is the CHECK lamp always turned on?
Go to Step 2Go to Step 3
21. Turn off the starter switch.
2. Disconnect the ECU connector.
3. Turn on the starter switch.
Is the CHECK lamp always turned on?The CHECK
circuit is
short-circuited to
GND. Repair the
circuit.
Go to Step 7
The ECU has
failed. Replace
the ECU.
Go to Step 7
3Turn on the starter switch.
Is the CHECK lamp always turned off?
Go to Step 4Go to Step 6
4Turn on the starter switch.
Is the battery voltage observed between terminals 30 and 19?
Go to Step 5
The CHECK
circuit wires are
broken or the
CHECK lamp is
failed. Repair the
circuit.
Go to Step 7
5Turn off the starter switch.
Is the battery voltage observed between terminals 30 and 19?The battery is
short±circuited.
Repair the
CHECK lamp
circuit.
Go to Step 7
The ECU has
failed. Replace
the ECU.
Go to Step 7
6Turn on the starter switch.
Does the CHECK lamp go off two seconds after?The phenomenon
is not reproduced
Refer to
ªTroubles
intermittently
observedº.
Go to Step 7
Go to Step 7
71. Check that all the parts are mounted.
2. Clear the trouble code.
Is this step complete?
Repeat the
ªDiagnosis Flowº.
Return to Step 7

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±58
Trouble Diagnosis Depending on The
Status of TOD Indicator
Functional check with TOD indicator light is conducted
prior to check on Charts A±H.

After the starter is switched on, check and see if the
status has become as tabulated below.
C07RW012

If the status is as tabulated above, there is no
problem. If not as tabulated above, inspect the
harness.

4B2±59 DRIVE LINE CONTROL SYSTEM (TOD)
Chart AIndicator drive circuit
Function of circuitThe circuit informs the indicator of the working condition of the ECU.
Fail conditionAll the TOD indicator lamps and CHECK lamp are lit, and go off momentarily at an inter-
val of about two seconds.
Indicator lamp status
Ð
Transfer positionTOD, 4LÐ
D04RW062