1998 ISUZU TROOPER check engine

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±30
Diagnostic Trouble Codes
CodeItemDiagnosisCheck flow No.
12Start codeNormalÐ
13RefShorted GND6
14Front speed sensorInput abnormality (open, sig or com)2
15RefShorted VB6
16Front speed sensorInput abnormality3
21TPSShorted or disconnected wiring, abnormality in
input7
23ECUCPU abnormality1
24Rear speed sensorInput abnormality (open, sig or com)5
25CHECK lampShorted14
26EMC (+)Shorted GND10
27Rear speed sensorInput abnormality4
28ADC (+) & AXLE SWOutput abnormality11
31EMC (+)Shorted or disconnected coil/wiring9
32ADC (+)Shorted or disconnected coil/wiring12
33ADC (+)Shorted GND13
34D-G MAPInput abnormality8
35CHECK lampShorted or disconnected wiring14
36ECUCPU abnormality1
37ECUCPU abnormality1
38ECUCPU abnormality1
TPS : Throttle Position Sensor
EMC : Electromagnetic coil
ADC : Shift on the fly (Axle Dis Connect)
D-G MAP : Discrimination engine type

4B2±33 DRIVE LINE CONTROL SYSTEM (TOD)
StepActionYe sNo
11. Start the engine.
2. Select 4H (TOD) mode.
Is the memory except DTC 14?
Go to Step 3Go to Step 2
2Is the continuity harness of terminal 24 (vehicle side terminal of
the front speed sensor)?Replace speed
sensor.
Go to Step 6
Repair the circuit.
Go to Step 6
3Is the memory DTC 24?
Go to Step 4
Refer to other
trouble check
flow.
Go to Step 2
4Is the continuity between harness of terminal 23 and 24 (vehicle
side terminal of the front and rear speed sensor)?
Go to Step 5
Repair the circuit.
Go to Step 6
5Is the continuity between harness of terminal 18 and 15 (vehicle
side terminal of the speed sensor COM and ref)?Replace front and
rear speed
sensor.
Go to Step 6
Repair the circuit.
Go to Step 6
61. Check that all the parts are mounted.
2. Clear the trouble code.
Is the step complete?
Repeat the
ªDiagnosis Flowº.
The trouble is not
reproduced.
Refer to
ªTroubles
intermittently
observedº.
Return to Step 6

4B2±39 DRIVE LINE CONTROL SYSTEM (TOD)
StepActionYe sNo
11. Start the engine.
2. Select 4H (TOD) mode.
Is the memory except DTC 24?
Go to Step 3Go to Step 2
2Is the continuity harness of terminal 23 (vehicle side terminal of
the rear speed sensor)?Replace speed
sensor.
Go to Step 6
Repair the circuit.
Go to Step 6
3Is the memory DTC 14?
Go to Step 4
Refer to other
trouble cheek
flow.
Go to Step 2
4Is the continuity between harness of terminal 23 and 24 (vehicle
side terminal of the front and rear speed sensor)?
Go to Step 5
Repair the circuit
Go to Step 6
5Is the continuity between harness of terminal 15 and 18 (vehicle
side terminal of the speed sensor COM and ref)?Replace front and
rear speed
sensor.
Go to Step 6
Repair the circuit.
Go to Step 6
61. Check that all the parts are mounted.
2. Clear the trouble code.
Is the step complete?
Repeat the
ªDiagnosis Flowº.
The trouble is not
reproduced.
Refer to
ªTroubles
intermittently
observedº.
Return to Step 6

4B2±41 DRIVE LINE CONTROL SYSTEM (TOD)
StepActionYe sNo
11. Start the engine.
Does the voltage between terminals 15 and 19 meet the standard
5V?
Go to Step 8Go to Step 2
2Is the voltage below the standard?Go to Step 3Go to Step 7
31. Turn off the starter switch.
2. Disconnect the ECU connector.
Is the continuity established between vehicle harness terminals
(B±67)7 and (B±67)11?
Go to Step 4
The ECU is
failed. Replace
the ECU.
Go to Step 8
41. Disconnect the H-49 connector.
Is the continuity established between floor harness connector
terminals (H-49)3 and (H-49)9?
Go to Step 5Go to Step 6
51. Disconnect the A±3 connector.
Is the continuity established between transfer harness connector
terminals (A±3)2 and (A±3)7?
Replace the front
speed sensor.
Go to Step 8
The reference
harness for the
front speed
sensor is
short±circuited to
GND. Repair the
circuit.
Go to Step 8
61. Disconnect the A±3 connector.
Is the continuity established between transfer harness connector
terminals (A±3)1 and (A±3)7?
Replace the rear
speed sensor.
Go to Step 8
The reference
harness for the
rear speed
sensor is
short±circuited to
GND. Repair the
circuit.
Go to Step 8
71. Turn off the starter switch.
2. Disconnect the ECU connector.
3. Turn on the starter switch.
Is the battery voltage observed between harness connector
terminals (B±67)7 and (B±67)11?
Repair the
harness circuit.
Go to Step 8
The ECU has
failed. Replace
the ECU.
Go to Step 8
81. Check that all the parts are mounted.
2. Clear the trouble code.
Is this step complete?
Repeat the
ªDiagnosis Flowº
Go to Step 8

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±44
Check flowTrouble codePhenomenonStandard
834The diesel/gasoline engine identifi-
cation signal is faulty.Gasoline: Continuity established
The engine identification signals of 6VE1 and 4JX1 are
changed each other.
D04RW056

4B2±47 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)4 and
(B±67)12?
Go to Step 2Go to Step 4
21. Connect the ECU connector.
2. Start the engine.
3. Set the TOD mode.
Does the voltage between terminals 4 and 20 indicate at least
0.4V?
Go to Step 3
The ECU has
failed. Replace
the ECU.
Go to Step 5
3Is the battery voltage always observed between terminals 4 and
20?
The harness is
short±circuited on
the battery.
Repair the circuit.
Go to Step 5
The phenomenon
is not
reproduced.
Refer to
ªTroubles
intermittently
observedº.
Go to Step 5
41. Disconnect the M±27 connector.
Is the continuity established between transfer connector
terminals (A±3)8 and (A±3)7?
The harness is
broken. Repair
the circuit.
Go to Step 5
Replace the
transfer
electromagnetic
coil (solenoid
clutch).
Go to Step 5
51. Check that all the parts are mounted.
2. Clear the trouble code.
Is this step complete?
Repeat the
ªDiagnosis Flowº.
Return to Step 5

4B2±49 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 (B±67)4 and (B±67)12?
indicate 1.0 to 5.0 ohm?
Go to Step 2Go to Step 3
21. Connect the ECU connector.
2. Start the engine.
3. Set the TOD mode.
When the throttle is operated between full close and full open
positions, does the voltage between terminals 4 and 20 indicate at
least 0.1 to 1.0 V?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
3Does the resistance between transfer connector terminals (A±3)8
and (A±3)7 indicate 1.0 to 5.0ohm?
The harness is
broken. Repair
the circuit.
Go to Step 4
Replace the
transfer
electromagnetic
coil.
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±88
StepActionYe sNo
1Are the front and rear tires in specified size?
Go to Step 2
Replace the tires
with specified
ones, and service
the new tires.
Go to Step 16
2Is the tire pressure correct?
Go to Step 3
Replace the tires
with specified
ones, and service
the new tires.
Go to Step 16
3Are the tires free from abnormal wear?
Go to Step 4
Replace the tires
with specified
ones, and service
the new tires.
Go to Step 16
4Are different types of tires used?
Go to Step 5
Replace the tires
with specified
ones, and service
the new tires.
Go to Step 16
51. Start the engine.
2. Shift the transfer lever to the high (TOD) position.
3. Fully turn the steering to the left (or right) end, and select the D
range and start the creep run.
Does the tight corner braking occur? Is the judder with chug-chug
sound observed? * Use caution on the operation.
Go to Step 6 Go to Step 11
61. Shift the transfer lever to the 2H position.
2. Fully turn the steering to the left (or right) end, and select the D
range and start the creep run.
Does the tight corner braking occur? Is the judder with chug-chug
sound observed? * Use caution on the operation.
Go to Step 7 Go to Step 14
7Is an LSD mounted to the rear differential? Go to Step 8 Go to Step 9
8Is the genuine LSD oil used in the rear differential?
Go to Step 9
Replace the
differential oil.
Go to Step 16
9Does the engine output the power correctly?
Go to Step 10
Check the
engine.
Go to Step 16
10Do the speed sensors work correctly? (Check trouble codes.)The ECU has
failed. Replace
the ECU.
Go to Step 16
Replace the
speed sensors.
Go to Step 16
11Is the tight corner braking observed only when the brake is
applied?
Go to Step 12
Conduct full
steering under
WOT.
Go to Step 5
121. Turn off the starter switch.
2. Disconnect the ECU connector.
Is the battery voltage observed between terminals (B±68)6 and
(B±67)11?
Go to Step 13
Repair the circuit
of terminal 6
(ABS IN).
Go to Step 16