front drive axle ISUZU TROOPER 1998 Service Owner's Manual

4B1±30
DRIVE LINE CONTROL SYSTEM (SHIFT ON THE FLY)
Front Axle Diagnosis

When the 4WD switch is operated from 4H to 2H,
indicator light does not go out.
Step
ActionYe sNo
1Drive slow 100 Ð 200m after a few minutesº idling.
Has indicator light gone out?
All right.Go to Step 2
2Jack up front tires.
Does the right side of front wheel rotate when the left side of front
wheel is rotated?
Go to Step 4Go to Step 3
31. Check the actuator switch.
2. Check the circuit to indicator.
Was a problem found?
Trace this chart
from the start
after repair or
replace.
Disassemble axle
ASM for check.
Trace this chart
from the start
after repair or
replace.
41. Check the VSV valve.
2. Check the circuit to VSV valve.
Was a problem found?Trace this chart
from the start
after repair or
replace.
Go to Step 5
5Is vacuum piping all right? (tank, hose, & pipe damage or trouble)
Go to Step 6
Trace this chart
from the start
after repair or
replace.
6Does actuator work all right?
Trace this chart
from the start.
Disassemble axle
ASM for check.
Trace this chart
from the start
after repair or
replace.

4B1±31 DRIVE LINE CONTROL SYSTEM (SHIFT ON THE FLY)

When the 4WD switch is operated from 2H to 4H,
indicator light is not actuated.
Step
ActionYe sNo
1Drive slow 100 Ð 200m after a few minutesº idling.
Has indicator light actuated?
All right.Go to Step 2
2Jack up front tires.
Does not the right side of front wheel rotate when the left side of
front wheel is rotated?
Go to Step 4Go to Step 3
31. Check the actuator switch.
2. Check the circuit to indicator.
Was a problem found?
Trace this chart
from the start
after repair or
replace.
Disassemble axle
ASM for check.
Trace this chart
from the start
after repair or
replace.
41. Check the VSV valve.
2. Check the circuit to VSV valve.
Was a problem found?Trace this chart
from the start
after repair or
replace.
Go to Step 5
5Is vacuum piping all right? (tank, hose, & pipe damage or trouble)
Go to Step 6
Trace this chart
from the start
after repair or
replace.
6Does actuator work all right?
Trace this chart
from the start.
Disassemble axle
ASM for check.
Trace this chart
from the start
after repair or
replace.

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±24
No.NAMECONTENTS
1VIGPower supply (IG)
2N.CNot used
34WD OUT4WD signal output
4SOL (+)Electromagnetic solenoid
5ADC (+)Axle disconnect output
6LIGHTING SWLighting SW input
7BRAKEBrake SW input
84H SW4H SW input
94L SW4L SW input
10AXEL SWAXEL SW input
11ABS INOperation signal input
12TOD SWTOD SW input
13DIAGSelf-diagnosis input
14D-G MAPD-G MAP recognition input (Only V6 engine)
15Ref.Vehicle speed sensor supply
16N.CNot used
17US/JAPDestination recognition input
18COM (±)Vehicle speed sensor GND
19S-GNDSensor GND
20P-GNDPower GND
21TPSThrottle position sensor
22TECH 2TECH 2 output
23Rer. SigRear vehicle speed sensor input
24Frt. SigFront vehicle speed sensor input
25IND.a4WD disply signal a
26IND.b4WD display signal b
27IND.c4WD display signal c
28IND.AUTOAUTO display output
29IND RrRear display output
30CHECKTOD warning lamp

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±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±78
StepNo Ye s Action
15When the transfer lever is shifted to the high position and 4WD
switch shifted to 4WD position, is 0V observed on each VSV?
Go to Step 16
Repair the circuit
or replace the
VSV.
Go to Step 19
16When the transfer lever is shifted to the 4L position, is 0V
observed on each VSV?
Go to Step 17
Repair the circuit
or replace the
VSV.
Go to Step 19
17Is the vacuum pressure supplied to the VSV?
Go to Step 18
Repair the
vacuum system.
Go to Step 19
18Can the single AXLE switch enable and disable the continuity?
Repair the shift
on the fly system
(refer to Section
4C ªFront Axleº.
Go to Step 19
Replace the
AXLE switch
(refer to Section
4C ªDrive Shaft
Systemº of
Chassis Repair
Manual).
Go to Step 19
19Check that all the parts are mounted.
Is this step complete?Repeat the
ªDiagnosis Flowº.
Return to Step 19

4B2±81 DRIVE LINE CONTROL SYSTEM (TOD)
StepNo Ye s Action
16When the transfer lever is shifted to the 4L position, is 0V
observed on each VSV?
Go to Step 17
Repair the circuit
or replace the
VSV.
Go to Step 19
17Is the vacuum pressure supplied to the VSV?
Go to Step 18
Repair the
vacuum system.
Go to Step 19
18Can the single AXLE switch enable and disable the continuity?
Repair the shift
on the fly system
Refer to Section
4C ªFront Axleº.
Go to Step 19
Replace the
AXLE switch
Refer to Section
4C ªDrive Shaft
Systemº.
Go to Step 19
19Check that all the parts are mounted.
Is this step complete?Repeat the
ªDiagnosis Flowº.
Return to Step 19

DRIVE LINE CONTROL SYSTEM (TOD) 4B2±86
Diagnosis from Symptom
Troubles that are not indicated by the warning lamp are
listed in the table below. These troubles are caused by
the faults that cannot be detected by the self-diagnostic
function of the control unit.
If this type of trouble is observed, interview the customer
and conduct test runs to reproduce the trouble,cross-check the reported trouble with the listed
phenomena, and diagnose and analyze the trouble on the
item by item basis.
PhenomenaMajor causeCorrective action
1The tight corner braking is ob-
served when the vehicle is subject
to full steering.
The standard tires are not used.

The tire pressure is incorrect.

The tires are worn inuniformity.

The transfer or wiring is
imperfect.

The limited slip differential is
failed.Check and recondition the ve-
hicle according to Chart 1.
2Even if the 4WD SW is select to the
4WD position, the 4WD mode is not
active, resulting in remarkable rear
wheel spin.
The transfer or wiring is
imperfect.

The shift on the fly system is
failed.Check and recondition the ve-
hicle according to Chart 2.
3
When the 4WD SW is select to
the 4WD position, the drive
resistance of the 4WD system is
too large to get sufficient running
speed.

Noised drive line.
The standard tires are not used.

The tire pressure is incorrect.

The tires are worn inuniformity.

The transfer or wiring is
imperfect.

The limited slip differential is Check and recondition the ve-
hicle according to Chart 1.
4The shift on the fly system (front
axle) generates gear noises.
The wiring is imperfect.

The full automatic free wheel
hub is failed.Check and recondition the ve-
hicle according to Chart 3.
5The braking distance gets long
even when the ABS is active.
The wiring is imperfect.

The ABS is failed.Check and recondition the ve-
hicle according to Chart 4.

4B2±93 DRIVE LINE CONTROL SYSTEM (TOD)
StepActionYe sNo
1Do the indicator lamps show the correct status?
Go to Step 2
Examine the
trouble based on
ªDiagnosis from
Trouble Codesº.
Go to Step 2
2Is any of the trouble codes 28, 32 and 33 recorded?Examine the
trouble based on
ªDiagnosis from
Trouble Codesº.
Go to Step 6
Go to Step 3
3Turn on the starter switch.
Is the battery voltage observed between terminals 1 and 20?
Go to Step 4Go to Step 5
4When the 4WD SW is select to the 2WD position, are the front
axle gears correctly disengaged (and when the left front tire is
jacked up and turned, is the front propeller shaft standstill)?The phenomenon
is not
reproduced.
Refer to
ªTroubles
intermittently
observedº.
Go to Step 6
The shift on the
fly system is
failed (refer to
Section 4C ªDrive
Shaft Systemº.
Go to Step 6
5Does the battery voltage maintain the correct level?
Repair the battery
circuit.
Go to Step 6
Repair the battery
and charging
system.
Go to Step 6
6Check that all the parts are mounted.
Is this step complete?Repeat the
ªDiagnosis Flowº.
Return to Step 6

4C±1 DRIVE SHAFT SYSTEM
DRIVELINE/AXLE
DRIVE SHAFT SYSTEM
CONTENTS
Service Precaution 4C±2. . . . . . . . . . . . . . . . . . . . . .
General Description 4C±2. . . . . . . . . . . . . . . . . . . . .
Diagnosis 4C±3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Rear Axle Shaft 4C±4. . . . . . . . . . . . . . . . . . . . . . . . .
Rear Axle Shaft and Associated Parts 4C±4. . . .
Removal 4C±4. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 4C±5. . . . . . . . . . . . . . . . . .
Oil Seal Replacement 4C±6. . . . . . . . . . . . . . . . . .
Installation 4C±6. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Special Tools 4C±8. . . . . . . . . . . . . . . . . . . . . . . . . . .
Front Hub and Disc (with Shift on the Fly) 4C±9. .
Disassembled View 4C±9. . . . . . . . . . . . . . . . . . . .
Disassembly 4C±9. . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 4C±10. . . . . . . . . . . . . . . . . .
Reassembly 4C±11. . . . . . . . . . . . . . . . . . . . . . . . . .
Front Hub and Disc with Manual Locking Hub 4C±14
Disassembled View 4C±14. . . . . . . . . . . . . . . . . . . .
Disassembly 4C±14. . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 4C±16. . . . . . . . . . . . . . . . . .
Reassembly 4C±16. . . . . . . . . . . . . . . . . . . . . . . . . .
Main Data and Specifications 4C±20. . . . . . . . . . . . .
Special Tools 4C±21. . . . . . . . . . . . . . . . . . . . . . . . . . .
Front Drive Shaft Joint 4C±22. . . . . . . . . . . . . . . . . . .
Front Drive Shaft Joints Replacement 4C±22. . . .
Front Axle Drive Shaft 4C±23. . . . . . . . . . . . . . . . . . .
Front Axle Drive Shaft and Associated
Parts 4C±23. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disassembly 4C±24. . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 4C±25. . . . . . . . . . . . . . . . . .
Bushing Replacement 4C±25. . . . . . . . . . . . . . . . . . Reassembly 4C±26. . . . . . . . . . . . . . . . . . . . . . . . . .
Shift On The Fly System 4C±28. . . . . . . . . . . . . . . . .
Shift On The Fly System and Associated
Parts 4C±28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disassembly 4C±28. . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 4C±30. . . . . . . . . . . . . . . . . .
Main Data and Specifications 4C±35. . . . . . . . . . .
Special Tools 4C±36. . . . . . . . . . . . . . . . . . . . . . . . . .
Front Propeller Shaft 4C±37. . . . . . . . . . . . . . . . . . . . .
General Description 4C±37. . . . . . . . . . . . . . . . . . . . .
Front Propeller Shaft and Associated Parts 4C±38
Removal 4C±38. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 4C±39. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disassembly (Except TOD 4y4) 4C±40. . . . . . . . .
Universal Joint Disassembly 4C±41. . . . . . . . . . . .
Inspection and Repair 4C±42. . . . . . . . . . . . . . . . . .
Universal Joint Reassembly 4C±45. . . . . . . . . . . . .
Reassembly (Except TOD 4y4) 4C±46. . . . . . . . . .
Main Data and Specifications 4C±47. . . . . . . . . . .
Rear Propeller Shaft 4C±48. . . . . . . . . . . . . . . . . . . . .
General Description 4C±48. . . . . . . . . . . . . . . . . . . . .
Rear Propeller Shaft and Associated Parts 4C±48
Removal 4C±49. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 4C±49. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disassembly 4C±50. . . . . . . . . . . . . . . . . . . . . . . . . .
Universal Joint Disassembly 4C±51. . . . . . . . . . . .
Inspection and Repair 4C±52. . . . . . . . . . . . . . . . . .
Universal Joint Reassembly 4C±53. . . . . . . . . . . . .
Reassembly 4C±54. . . . . . . . . . . . . . . . . . . . . . . . . .
Main Data and Specifications 4C±55. . . . . . . . . . .