Isuzu Amigo / Axiom / Trooper / Rodeo / VehiCross. Manual - part 121

DRIVE LINE CONTROL SYSTEM (TOD)

4B2–102

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.

Phenomena

Major cause

Corrective action

The tight corner braking is
observed 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
vehicle according to Chart 1.

Even if the TOD switch is selected
to the TOD position, the F4WD
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
vehicle according to Chart 2.

When the TOD switch is
selected to the TOD position,
the drive resistance of the
F4WD system is too large to get
sufficient running speed.

Noised drive line.

The standard tires are not used.

The tires are worn inuniformity.

The transfer or wiring is
imperfect.

The limited slip differential is
failed.

Check and recondition the
vehicle according to Chart 1.

The shift on the fly system (front
axle disconnect) generates gear
noises.

The wiring is imperfect.

The shift on the fly system is
failed.

Check and recondition the
vehicle according to Chart 3.

The braking distance gets long
even when the ABS is active.

The wiring is imperfect.

The ABS is failed.

Check and recondition the
vehicle according to Chart 4.

The transfer does not change to the
low range from the high range.

The transfer or wiring is
imperfect.

The TOD switch is imperfect.

The AT inhibitor switch is
imperfect.

Check and recondition the
vehicle according to chart 5.

The transfer does not change to the
high range from the low range.

im erfect.

The brake switch is imperfect.

The engine speed signal is
imperfect.

The speed sensor is imperfect.

Check and recondition the
vehicle according to chart 6.

The transfer stays neutral and the
vehicle does not run.

The transfer is imperfect.

Check and recondition the
vehicle according to chart 7.

4B2–103

DRIVE LINE CONTROL SYSTEM (TOD)

Chart 1

The tight corner braking is observed.

Function of circuit

—

Fail condition

When the vehicle is subject to full steering in the TOD mode, the drive resistance gets

large or the judder occurs. Otherwise, the above phenomenon is observed only when the

brake is applied.

D04R200021

DRIVE LINE CONTROL SYSTEM (TOD)

4B2–104

Step

Action

Yes

Are 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

Is the tire pressure correct?

Go to

Step 3

Inflate the tires

with specified

pressure.

Go to

Step 16

Are 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

Are different types of tires used?

Go to

Step 5

Replace the tires

with specified

ones, and service

the new tires.

Go to

Step 16

1. Start the engine.
2. Select the TOD switch to the 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

1. Select the TOD switch 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

Is an LSD mounted to the rear differential?

Go to

Step 8

Go to

Step 9

Is the genuine LSD oil used in the rear differential?

Go to

Step 9

Replace the

differential oil.

Go to

Step 16

Does the engine output the power correctly?

Go to

Step 10

Check the

engine.

Go to

Step 16

Do 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

Is the tight corner braking observed only when the brake is
applied?

Go to

Step 12

Conduct full

steering under

WOT.

Go to

Step 5

1. Turn on the starter switch.

Is 8

∼

10 V observed between terminals 33 and 47?

Go to

Step 13

Repair the circuit

of the ECU

connector

terminal 33 (ABS

IN).

Go to

Step 16

4B2–105

DRIVE LINE CONTROL SYSTEM (TOD)

Step

Yes

Action

1. Apply the brake and fully turn the steering to the left (or right)

end, and start the creep run.

Does the voltage between terminals 11 and 22 range between 0.1
and 1.0V?

Repair the

transfer

assembly.

Go to

Step 16

The ECU has

failed. Replace

the ECU.

Go to

Step 16

1. Select the TOD switch to the TOD position.
2. Fully turn the steering to the left (or right) end, and select the D

range and start the creep run.

Does the voltage between terminals 11 and 22 range between 0.1
and 1.0V?

Go to

Step 15

Go to

Step 10

1. Select the TOD switch to the 2H position.
2. Jack up the right front wheel.

Does the front tire rotate smoothly?

The phenomenon

is not

reproduced.

Refer to

“Troubles

intermittently

observed”.

Repair the

transfer

assembly.

Go to

Step 16

Check that all the parts are mounted.

Is this step complete?

Verify the repair

Go to

Step 16

*NOTE: Before checking this item, run the vehicle more
than 10 meters with the steering wheel in straight position
so that the 4L mechanical lock sleeve can be released
certainly.

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