ISUZU TF SERIES 2004 Workshop Manual

ELECTRICAL-BODY AND CHASSIS 8A-353
TROUBLE SHOOTING
Rear defogger inoperative

Checkpoint Trouble Cause Countermeasure


Reinstall or replace the fuse
No. C-7 (15A) and 9
B-56


Poor fuse contact or blown
NG

Reinstall or replace the fuse
SBF-10 (20A)

SBF-10 (20A, Fuse box)

Poor fuse contact or blown


Replace the rear defogger
switch

Rear defogger switch function

Switch malfunction
NG NG OK
OK OK

Fuse No. C-7 (15A, Fuse box)
and 9
B-56


Replace the rear defogger
relay

Relay malfunction
NG
Continued on the next page

Rear defogger relay function


Repair grounding point
D-2
contact

Grounding point
C-2


Poor grounding point contact
NG OK
Repair open circuit or poor
connector contact between
fuse No. C-7 (15A) and 3
B-7, SBF-10 (20A) and 1
B-7, 2 B-7 (3 B-55) and
1
L-4, 4 B-7 (3 B-54)
and 3
B-46 or 1 B-46 and

C-2
Voltage between 1 L-4-
ground when the starter switch
and the rear defogger switch
are at on position (should be
battery voltage present)
Open circuit or poor connector
contact
NG OK

8A-354 ELECTRICAL-BODY AND CHASSIS
Checkpoint Trouble Cause Countermeasure


OK
Repair open circuit or
connector contact between 1
L-7 and C-2

Open circuit or poor connector
contact
NG
Continued from the previous page

Continuity between 1
L-7
and
C-2


Repair heat wire

Continuity between rear
defogger terminals

Broken heat wire of rear
defogger
NG OK

ELECTRICAL-BODY AND CHASSIS 8A-355
REMOVAL AND INSTALLATION

865R300008


REAR DEFOGGER SWITCH
Removal
1. Instrument Panel Cluster Assembly

Refer to Section 10 “BODY” for center cluster panel
assembly removal steps.
2. Rear Defogger Switch (With HVAC control unit)
Refer to Section 1 “HVAC” HVAC control unit assembly
removal steps.



Installation
Follow the removal procedure in the reverse order to install the
rear defogger switch.

8A-356 ELECTRICAL-BODY AND CHASSIS
INSPECTION AND REPAIR





Switch side
B-57


REAR DEFOGGER SWITCH
Rear Defogger Switch Connections

Terminal No.
SW position 9 7 8
ON
OFF

B-7


REAR DEFOGGER RELAY
Check continuity between the relay terminals.
2- 1......................... No continuity
(When battery voltage is applied between
4 and 3)
2- 1......................... Continuity


INSPECTION OF REAR DEFOGGER HEAT
WIRE

Heat wires are printed on the inner side of glass.
To clean, use a soft cloth and wipe horizontally along the
wires.

Never use glass cleaner or equivalent.

When measuring voltage, wind a piece of tin foil around the
tip of the negative probe and press the foil against the wire
with your finger as shown.



(1) Turn the ignition switch on.
(2) Turn the defogger switch on.
(3) Measure the voltage between the three points on the hea
t
wire and the (-) terminal with a voltmeter.
(4) Check that the voltage becomes smaller from
A to B to C.

ELECTRICAL-BODY AND CHASSIS 8A-357


(5) If there is a place where the voltage suddenly changes to
0V, there is a broken wire between there and the powe
r
side.
(6) Move the tester probe from the position where the voltage
changes to 0V toward the power side and find where the
voltage suddenly increases.



REPAIR OF BROKEN HEAT WIRE
(1) Clean broken wire tips with white gasoline.
(2) Place masking tape along both sides of wire to be repaired.



(3) Thoroughly mix the repair agent (Dupont paste No. 4817 or
equivalent).
(4) Using a fine tip brush, apply a small amount to the wire.
(5) After a couple of minutes, remove the masking tape.
(6) Allow to stand at least 24 hours.

8A-358 ELECTRICAL-BODY AND CHASSIS
SRS-AIR BAG
PARTS LOCATION (RHD)






RTW48AXF021201 & RTW48AXF021301

ELECTRICAL-BODY AND CHASSIS 8A-359

PARTS LOCATION (LHD)






RTW48AXF021401 & RTW48AXF021501

8A-360 ELECTRICAL-BODY AND CHASSIS

CIRCUIT DIAGRAM




RTW48AXF024101

ELECTRICAL-BODY AND CHASSIS 8A-361
TRANSFER CASE CONTROL MODULE
PARTS LOCATION (RHD)






RTW48AXF021701 & RTW48AXF021801

8A-362 ELECTRICAL-BODY AND CHASSIS

PARTS LOCATION (LHD)






RTW48AXF021901 & RTW48AXF022001