ISUZU TROOPER 1998 Service Repair Manual

8DÐ138 WIRING SYSTEM
1-2. Headlight On The Left (Or Right) Side Inoperative
1-3. Both Headlights In Low-Beam Inoperative
YES
·IS THE HEADLIGHT BULB ON THE LEFT (OR RIGHT)
SIDE NORMAL?
YES
REPLACE THE FUSE
NO
·IS THE FUSE F-4 (15A) (OR F-5 (15A)) NORMAL?
REPAIR A POOR CONNECTION AT THE CONNECTORS OR AN
OPEN CIRCUIT BETWEEN
FUSE F-4 (15A) AND 3 C-21 (LH)
FUSE F-5 (15A) AND 3 C-32 (RH)REPLACE THE BULB
NO
·
YES
REPAIR A POOR CONNECTION AT THE CONNECTORS OR
AN OPEN CIRCUIT BETWEEN
13 B-12 AND 10 H-15REPAIR OR REPLACE THE DIMMER•PASSING SWNO
·WITH THE SWITCH AT THE LOW-BEAM POSITION, IS
THERE CONTINUITY BETWEEN THE SW CONNECTOR
TERMINALS 13 B-12 AND 16 B-12
DISCONNECT THE DIMMER•PASSING SW CONNECTOR
(COMBINATION SW)

WIRING SYSTEM 8DÐ139
1Ð4. Headlight Low-Beam On The Left (Or Right) Side Inoperative
·IS THE HEADLIGHT BULB ON THE
LEFT (OR RIGHT) SIDE NORMAL?
YES
·IS THE FUSE F–4 (15A) (OR F–5 (15A))
NORMAL?
YES
REPLACE THE BULB
NO
·DISCONNECT THE DIMMER·PASSING SW CONNECTOR
·WITH THE SWITCH AT THE LOW–BEAM POSITION, IS THERE
CONTINUITY BETWEEN 13 B–12 AND 16 B–12 ?
YES
REPLACE THE FUSE
NO
REPAIR A POOR CONNECTION AT THE CONNECTORS
OR AN OPEN CIRCUIT BETWEEN 3 C–21 AND F–4
(15A) (OR 3 C–32 AND F–5 (15A))
NO
REPAIR OR REPLACE THE DIMMER·PASSING SWREPAIR A POOR CONNECTION AT THE CONNECTORS OR AN
OPEN CIRCUIT BETWEEN 13 B–12 AND 1 C–21 (OR 13 B–12
AND 1 C–32 )
·IS THE CONTINUITY BETWEEN
3 C–21 AND F–4 (15A) (OR 3 C–32
AND F–5 (15A)) NORMAL?
NOYES

8DÐ140 WIRING SYSTEM
1Ð5. Both Headlights In High-Beam Inoperative
·DISCONNECT THE DIMMER•
PASSING SW CONNECTOR (COMBINATION SW)
YES
REPAIR A POOR CONNECTION AT THE CONNECTORS
OR AN OPEN CIRCUIT BETWEEN
15 B-12 AND 16 H-16REPAIR OR REPLACE THE DIMMER•
PASSING SW
NO
·WITH THE SWITCH AT HIGH-BEAM, IS THERE
CONTINUITY BETWEEN THE SWITCH CONNECTOR TERMINALS
15 B-12 AND 16 B-12 ?
1Ð6. Headlight High-Beam On The Left (Or Right) Side Inoperative
·IS THE HEADLIGHT BULB ON THE
LEFT (OR RIGHT) SIDE NORMAL?
YES
·IS THE FUSE F–4 (15A) (OR F–5 (15A))
NORMAL?
YES
REPLACE THE BULB
NO
·DISCONNECT THE DIMMER·PASSING SW CONNECTOR
·WITH THE SWITCH AT THE HIGH–BEAM POSITION, IS THERE
CONTINUITY BETWEEN 15 B–12 AND 16 B–12 ?
YES
REPLACE THE FUSE
NO
REPAIR A POOR CONNECTION AT THE CONNECTORS
OR AN OPEN CIRCUIT BETWEEN 3 C–21 AND F–4
(15A) (OR 3 C–32 AND F–5 (15A))
NO
REPAIR OR REPLACE THE DIMMER·PASSING SWREPAIR A POOR CONNECTION AT THE CONNECTORS OR AN
OPEN CIRCUIT BETWEEN 15 B–12 AND 2 C–21 (OR 15 B–12
AND 2 C–32 )
·IS THE CONTINUITY BETWEEN
3 C–21 AND F–4 (15A) (OR 3 C–32
AND F–5 (15A)) NORMAL?
NOYES

WIRING SYSTEM 8DÐ141
1-7. Headlight Beam Does Not Change
1-8. Headlights Remain On When The Lighting SW Is Turned Off
YES
·DISCONNECT THE DIMMER•PASSING
SWREPAIR OR REPLACE THE DIMMER•PASSING SW
NO
·DOES THE LEVER OF THE DIMMER•
PASSING SW OPERATE SMOOTHLY AND SECURELY?
·WITH THE SWITCH AT THE LOW-BEAM POSITION, IS
THERE CONTINUITY BETWEEN 13 B-12 AND 16 B-12 ?
ALSO, WITH IT AT THE HIGH-BEAM POSITION, IS THERE
CONTINUITY BETWEEN 15 B-12 AND 16 B-12 ?
NO
REPAIR OR REPLACE THE DIMMER•PASSING SW
YES
·REPLACE THE LIGHTING RELAY
NO
·IS THE LIGHTING RELAY NORMAL?
REPAIR OR REPLACE THE LIGHTING SW
NO
DISCONNECT THE LIGHTING SW CONNECTOR
·IS THE CONTINUITY BETWEEN
THE SWITCH CONNECTOR TERMINALS 1 B-12 AND
7 B-12 NORMAL?
YES
REPAIR A SHORT CIRCUIT BETWEEN
5 X-1 AND 1 B-12

8DÐ142 WIRING SYSTEM
REPAIR OR REPLACE THE LIGHTING SW
1-10. Passing Lights Inoperative
·DISCONNECT THE DIMMER•PASSING SW CONNECTOR
YES
REPAIR A POOR CONNECTION AT THE CONNECTORS
OR AN OPEN CIRCUIT BETWEEN 5 H-15 AND
14 B-12 REPAIR OR REPLACE THE SWITCH
NO
·WITH THE SWITCH AT PASSING POSITION, IS THERE
CONTINUITY BETWEEN THE SWITCH CONNECTOR TERMINALS
14 B-12 AND 16 B-12 , AND 15 B-12 AND 16 B-12 ?
1-9. Headlights Come On With The Lighting SW At The Clearance Light Position

WIRING SYSTEM 8DÐ143
2-1. Both Headlights Inoperative
·IS THE LIGHTING RELAY NORMAL?
YES
REPLACE THE RELAY
NO
·IS B-19 GROUNDED SECURELY?
YESNO
GROUND IT SECURELY·IS THE DIODE NORMAL ?
YESNO
REPLACE THE DIODE
·IS THE DIMMER RELAY NORMAL?
YESNO
REPLACE THE RELAY·
·DISCONNECT THE LIGHTING SW CONNECTOR
YESNO
·
·REMOVE THE LIGHTING SW
YESNO
REPAIR A POOR CONNECTION AT THE CONNECTORS
OR AN OPEN CIRCUIT BETWEEN THE FUSIBLE LINK
FL-1 (80A) AND 1 B-12
REPAIR OR REPLACE THE LIGHTING SW REPAIR A POOR CONNECTION AT THE CONNECTORS OR
AN OPEN CIRCUIT BETWEEN THE LIGHTING SW HARNESS SIDE
CONNECTOR 7 B-12 AND B-19
IS THE BATTERY VOLTAGE APPLIED BETWEEN THE
HARNESS SIDE CONNECTOR 1 B-12 AND GROUND?
IS THERE CONTINUITY BETWEEN 1 B-12 AND 7 B-12 WHEN
SETTING THE LIGHTING SW AT THE HEADLIGHT POSITION?

8DÐ144 WIRING SYSTEM
2-2. Headlight On The Left (Or Right) Side Inoperative
·IS THE HEADLIGHT BULB ON THE LEFT (OR RIGHT) SIDE
NORMAL?
YES
REPLACE THE BULB
NO
·IS 7 C-39 (OR 5 C-39 ) GROUNDED SECURELY? (RH)
IS 4 C-39 (OR 7 C-16 ) GROUNDED SECURELY? (LH)
YESNO
GROUND IT SECURELY
REPAIR AN OPEN CIRCUIT BETWEEN
3 C-32 AND 7 C-39 (OR 5 C-39 ) (RH)
3 C-21 AND 4 C-39 (OR 7 C-16 ) (LH)
·IS THE DIMMER RELAY NORMAL?
YES
REPAIR A POOR CONNECTION AT THE CONNECTORS OR
AN OPEN CIRCUIT BETWEEN 2 X-3 AND FUSE F-6 (10A)
NO
REPLACE THE RELAY
2-3. Both Headlights In Low-Beam Inoperative

WIRING SYSTEM 8DÐ145
2-4. Headlight Low-Beam On The Left (Or Right) Side Inoperative
2-5. Both Headlights In High-Beam Inoperative
·IS THE HEADLIGHT BULB NORMAL?
YESNO
REPLACE THE BULB·IS THE FUSE F-6 (10A) (OR F-7 (10A)) NORMAL?
YES
REPAIR A POOR CONNECTION AT THE CONNECTORS OR
AN OPEN CIRCUIT BETWEEN FUSE F-6 (10A) AND 1 C-21
(OR FUSE F-7 (10A) AND 1 C-32 )
NO
REPLACE THE FUSE
·IS THE DIMMER RELAY NORMAL?
YESNO
REPLACE THE RELAY·
·DISCONNECT THE DIMMER·PASING SW CONNECTOR
IS THERE ANY CONTINUITY BETWEEN THE SWITCH SIDE
CONNECTOR 15 B-12 AND 16 B-12 WHEN THE
SWITCH IS AT HIGH-BEAM POSITION?
YESNO
REPAIR OR REPLACE THE SWITCH·IS THE BATTERY VOLTAGE APPLIED BETWEEN THE
HARNESS SIDE CONNECTOR 15 B-12 AND GROUND
WHEN THE SWITCH IS AT HIGH-BEAM POSITION?
YESNO
REPAIR A POOR CONNECTION AT THE CONNEC-
TORS OR AN OPEN CIRCUIT BETWEEN 5 X-3
AND 15 B-12REPAIR A POOR CONNECTION AT THE CONNECTOR OR AN
OPEN CIRCUIT BETWEEN 3 X-3 AND FUSE F-4 (10A)

8DÐ146 WIRING SYSTEM
2-6. Headlight High-Beam On The Left (Or Right) Side Inoperative
2-7. Headlight Beam Does Not Change
·IS THE CONTINUITY IN THE DIMMER·PASSING
SW NORMAL ?
YES
REPAIR OR REPLACE THE SWITCH
NO
·IS B-19 GROUNDED SECURELY?
YESNO
GROUND IT SECURELY
REPAIR A POOR CONNECTION AT THE CONNECTORS OR
AN OPEN CIRCUIT BETWEEN 5 X-3 AND 15 B-12
·IS THE DIMMER RELAY NORMAL?
YESNO
REPAIR AN OPEN CIRCUIT BETWEEN 16 B-12 AND
B-19
REPLACE THE RELAY·IS THERE CONTINUITY BETWEEN 16 B-12 AND
B-19 ?
YESNO
·IS THE HEADLIGHT BULB NORMAL?
YESNO
REPLACE THE BULB·IS THE FUSE F-4 (10A) (OR F-5 (10A)) NORMAL?
YES
REPAIR A POOR CONNECTION AT THE CONNECTORS OR
AN OPEN CIRCUIT BETWEEN
(LH) FUSE F-4 (10A) AND 2 C-21
(RH) FUSE F-5 (10A) AND 2 C-32
NO
REPLACE THE FUSE

WIRING SYSTEM 8DÐ147
2-8. Headlights Remain On When The Lighting SW Is Turned Off
2-9. Headlights Come On When The Lighting SW At The Clearance Light Position
·IS THE LIGHTING RELAY NORMAL?
YES
REPLACE THE RELAY
NO
·
·DISCONNECT THE LIGHTING SW CONNECTOR
YESNO
REPAIR OR REPLACE THE LIGHTING SW
REPAIR A SHORT CIRCUIT BETWEEN 5 X-1
AND 1 B-12
IS THE CONTINUITY BETWEEN THE SWITCH CONNECTOR
TERMINALS 1 B-12 AND 7 B-12 NORMAL?
REPAIR OR REPLACE THE LIGHTING SW
2-10. Passing Lights Inoperative
·
·DISCONNECT THE DIMMER·PASSING SW CONNECTOR
YESNO
REPAIR OR REPLACE THE SWITCH
REPAIR A POOR CONNECTION AT THE CONNECTORS OR
AN OPEN CIRCUIT BETWEEN 4 H-12 AND 14 B-12
WITH THE AT PASSING POSITION, IS THERE CONTINUITY
BETWEEN THE SWITCH CONNECTOR TERMINALS 14 B-12
AND 16 B-12 , AND 15 B-12 AND 16 B-12 ?