Isuzu Amigo / Axiom / Trooper / Rodeo / VehiCross. Manual - part 1143

DRIVELINE CONTROL SYSTEM

4B–5

Warning at “4L” position : Shifting from 4WD to 2WD
while at “4L” operation is not possible. While at 4WD in
the   “4L”operation, the transfer position switch cannot
be deactivated. If the 4WD switch was pressed to

deactivate the 4WD operation while in "4L", then the
4WD indicator lamp will blink faster (from 2Hz to   4Hz)
to alert the driver of the wrong operation and the 4WD to
2WD mode will cancel. 

Time Chart of Shifting from 4WD to 2WD at “4L” Condition

F04R100003

4WD out signal to other Electronic Hydraulic
Control Unit : ECU of shift on the fly sends 4WD out
signal to other Electronic Hydraulic Control Unit as
below.

4WD out signal

(Period)

Vehicle Condition

Transfer position switch

Front axle switch

120 ms

2WD

2WD (Open)

2WD (Open)

240 ms

4WD

4WD (Close)

4WD (Close)

4B–6

DRIVELINE CONTROL SYSTEM

Functions of Indicator Lamp

Indication of vehicle condition : Indicator lamp is
controlled by transfer ECU of shift on the fly and shows
vehicle conditions as below.

Bulb check :The bulb of indicator lamp is checked for 2
seconds when ignition key is turned on.

Time Chart of Bulb Checking

F04RW004

Retrials from 2WD to 4WD :Sometimes shifting from
2WD to 4WD may not occur when in severe cold
weather   conditions or under high speed conditions.
Should this occur, the 4WD indicator lamp will flash
continously until the driver disengages the 4WD
operation (see Retrial for more information). 

Indicator

Vehicle condition

4WD switch

Transfer position 

switch

Front axle switch

Off

2WD

Off (Close)

2WD (Open)

2WD (Open)

On

4WD

On (Open)

4WD (Close)

4WD (Close)

Blink (2Hz)

Operating

On (Open)

4WD (Close)

2WD (Open)

Off (Close)

2WD (Open)

4WD (Close)

Blink (4Hz)

Stop operating

On (Open)

2WD (Open)

2WD (Open)

Off (Close)

4WD (Close)

4WD (Close)

DRIVELINE CONTROL SYSTEM

4B–7

Diagnosis

Before Judging That Troubles Occur
(Unfaulty mode)

When Switching from 2WD to 4WD

1. In case that blinking frequency of the 4WD

indicator changes from 2Hz to 4Hz.
When heavy synchronization load is needed, the
motor actuator repeats the transfer   gear shifting up
to 3 times. The 4WD indicator lamp will blink (2Hz)
while the motor actuator attempts   shifting. If after
the 3rd attempt the shifting fails, the 4WD indicator
lamp will blink faster (4Hz) and   the motor actuator
will return to 2WD mode. 
Heavy synchronization load occurs when: 

• At severe low temperatures. 

• Higher rotational difference in speed between the

front wheels and axles during   cornering. 

Solution 1: Attempt the 4WD mode again at a
lower speed or when the vehicle is at a stop. 

2. In case that the 4WD indicator continues

blinking at 2Hz for more than 11.5 seconds.
When there is rotational difference in speed
between the front wheels and axles, the front
wheels and   the front axles may have difficulty
engaging. The blinking 4WD indicator lamp (at 2Hz)
will indicate   that the transfer case is shifting into
the 4WD mode, however it will blink faster (4Hz) if
shifting into   4WD mode is impossible, unless
rotational difference and phase difference does not
exist. 
Solution 2: If the vehicle is moving, drive the
vehicle straight while accelerating and
decelerating, and if the vehicle is at a stop,
move the vehicle forward and backward for 2 to
3 meters. 

When Switching from 4WD to 2WD

1. When the 4WD indicator lamp continues to blink

(at 2Hz). 
The 4WD indicator lamp continues to blink (at 2Hz)
until both shifting the transfer gear and
disconnecting the front wheels are completed when
switching 4WD to 2WD.  When drive line is loaded
with torsional torque, the shifting transfer gear and
disconnecting front wheels are impossible.  In this
case, removal of torsional  torque on drive line
makes the shifting transfer gear and disconnecting
front wheels possible.
Solution 3: If the vehicle is moving, drive the
vehicle straight while accelerating and
decelerating,   and if the vehicle is at a stop,
move the vehicle forward and backward for 2 to
3 meters. 

2. When the 4WD indicator lamp blinking pattern

changes (from 2Hz to 4Hz). 
Check the position of the transfer lever. Is it in the
“4L” position? Shifting from 4WD to   2WD while at
“4L” will not occur. 
Solution 4: Push the 4WD switch ON (to 4WD),
then shift the transfer lever to the “High”
position   and push the 4WD switch Off (to
engage to 2WD). 

4B–8

DRIVELINE CONTROL SYSTEM

Parts Location

828RY00008

EndOFCallout

Legend

(1) H–18
(2) E–56, E–57
(3) E–60
(4) I–1
(5) B–19
(6) B–8
(7) I–19

(8) H–15, H–17
(9) C–47

(10) C–16

(11) H–6

(12) C–49 (ADC CONTROL UNIT)
(13) E–30
(14) C–36