Isuzu Trooper (1998-2002 year). Service manual — part 944

8D–310

WIRING SYSTEM

Diagnosis

Quick Chart for Check Points

Check point

Fuse

C-5 (15A)

Wiper &

washer

SW

Alarm &

relay

control unit

Wiper

motor

Cable

harness

1

Windshield wiper does not operate at
any position

Trouble mode

2

Windshield wiper does not operate at
“INT” position

3

Intermittent interval does not change

4

Windshield wiper does not operate at
“LO” position

5

Windshield wiper does not operate at
“HI” position

6

Auto-stop function of the windshield
wiper motor does not operate

7

Rotation of the front wiper motor does
not stop

Washer

motor

8

Windshield washer motor does not
operate

WIRING SYSTEM

8D–311

1 Windshield Wiper Does Not Operate At Any Switch Position

REPAIR OR REPLACE THE SWITCH

•

IS FUSE C-5 (15A) NORMAL?

YES

•

•

•

DISCONNECT THE CONNECTOR OF THE WINDSHIELD WIPER &
WASHER SWITCH
TURN THE STARTER SWITCH ON
IS THERE ANY BATTERY VOLTAGE APPLIED BETWEEN THE
SWITCH HARNESS SIDE CONNECTOR 3 B-52 AND THE
GROUND?

REPLACE THE FUSE

NO

YES

NO

•

IS THE CONTINUITY IN THE WINDSHIELD WIPER & WASHER
SWITCH NORMAL?

REPAIR A POOR CONNECTION AT THE
CONNECTORS OR AN OPEN CIRCUIT BETWEEN THE
FUSE C-5 (15A) AND 3 B-52

YES

NO

•

IS 2 C-39 GROUNDED SECURELY?

YES

NO

•

•

•

DISCONNECT THE CONNECTOR OF THE WINDSHIELD WIPER MOTOR
WITH THE MOTOR CONNECTOR 2 C-38 CONNECTED TO
THE BATTERY (+) TERMINAL, AND THE CONNECTOR 3 C-38 TO
THE (–) TERMINAL, DOES THE MOTOR ROTATE AT A LOW
SPEED?
AND WITH THE CONNECTOR 1 C-38 CONNECTED TO THE (+)
TERMINAL, DOES THE MOTOR ROTATE AT A HIGH SPEED?

GROUND IT SECURELY

REPAIR A POOR CONNECTION AT THE CONNECTORS OR AN OPEN
CIRCUIT BETWEEN 3 C-38 AND THE GROUND

REPAIR OR REPLACE THE WINDSHIELD WIPER MOTOR

YES

NO

8D–312

WIRING SYSTEM

2 Windshield Wiper Does Not Operate At “INT” Position

•

•

•

DISCONNECT THE CONNECTORS OF THE WINDSHIELD WIPER &
WASHER SWITCH
SET THE SWITCH AT THE “INT” POSITION
IS THERE CONTINUITY BETWEEN THE SWITCH CONNECTOR
TERMINALS 3 B-52 AND 2 B-52 ?

YES

NO

•

•

•

DISCONNECT THE CONNECTOR OF THE ALARM & RELAY
CONTROL UNIT
SET THE WINDSHIELD WIPER & WASHER SWITCH AT THE "INT"
POSITION AND TURN THE STARTER SWITCH ON
IS THE BATTERY VOLTAGE APPLIED BETWEEN 20 B-7 AND
THE GROUND?

REPAIR A POOR CONNECTION AT THE CONNECTORS
OR AN OPEN CIRCUIT BETWEEN 14 B-52 AND B-19

YES

NO

•

IS B-19 GROUNDED SECURELY?

REPAIR OR REPLACE THE WINDSHIELD WIPER &
WASHER SWITCH

YES

NO

GROUND IT SECURELY

•

IS THERE CONTINUITY BETWEEN THE WINDSHIELD WIPER &
WASHER SWITCH HARNESS SIDE CONNECTOR TERMINALS
14 B-52 AND THE GROUND?

YES

NO

REPAIR A POOR CONNECTION AT THE CONNECTORS
OR AN OPEN CIRCUIT BETWEEN 2 B-52 AND 20 B-7

•

IS THERE CONTINUITY BETWEEN 14 B-6 AND 8 B-52 ?

YES

NO

REPAIR A POOR CONNECTION AT THE CONNECTORS
OR AN OPEN CIRCUIT BETWEEN 14 B-6 AND
8 B-52

REPLACE THE ALARM & RELAY CONTROL UNIT

WIRING SYSTEM

8D–313

3 Intermittent Interval Does Not Change

•

•

DISCONNECT THE CONNECTOR OF THE WINDSHIELD
WIPER & WASHER SWITCH
WHEN THE INTERMITTENT KNOB IS TURNED, DOES THE
RESISTANCE VALUE BETWEEN THE SWITCH CONNECTOR
TERMINALS 8 B-52 AND 14 B-52 VARY BETWEEN 0

Ω

- 2 K

Ω

?

YES

NO

REPAIR OR REPLACE THE SWITCH

IS THERE SHORT CIRCUIT BETWEEN 14 B-6 AND 8 B-52 ?

•

YES

NO

REPAIR A SHORT CIRCUIT

REPLACE THE ALARM & RELAY
CONTROL UNIT

4 Windshield Wiper Does Not Operate At “LO” Position

•

•

•

DISCONNECT THE CONNECTORS OF THE WINDSHIELD WIPER &
WASHER SWITCH
TURN THE STARTER SWITCH ON
SHORT CIRCUIT THE WINDSHIELD WIPER & WASHER SWITCH HAR-
NESS SIDE CONNECTOR TERMINALS 3 B-52 - 5 B-52 AND
CHECK TO SEE IF THE WINDSHIELD WIPER MOTOR ROTATES AT A
LOW SPEED.

REPAIR OR REPLACE THE WIPER & WASHER SWITCH