ISUZU TF SERIES 2004 Workshop Manual

ELECTRICAL-BODY AND CHASSIS 8A-163

PARTS LOCATION
RTW38DXF007501

8A-164 ELECTRICAL-BODY AND CHASSIS

PARTS LOCATION




RTW48AXF013001

ELECTRICAL-BODY AND CHASSIS 8A-165

CIRCUIT DIAGRAM




RTW48AXF027801

8A-166 ELECTRICAL-BODY AND CHASSIS
TROUBLESHOOTING
STOPLIGHT AND HIGH MOUNTED STOPLIGHT
1. One side of stoplight does not light

Checkpoint Trouble Cause Countermeasure


Replace the bulb or repair
connector contact

Burned out bulb or poor
connector contact
NG

Repair open circuit or
connector contact


Repair open circuit or
connector contact


Open circuit or poor connector
contact


Continuity between
9
H-9 - 2 F-6 (LH) (or
2
F-5 (RH))


Open circuit or poor connector
contact

Continuity between

C-109 - 4 F-6 (LH) (or
4
F-5 (RH)) NG NG OK
OK

Stoplight bulb continuity




2. Both sides of stoplight do not light



Adjust the switch installation
position

Stop light switch (or brake
switch) function

Incorrect the switch installation
or adjustment
NG

Repair open circuit or
connector contact
Voltage between 2 F-6
ground or 2
F-5 - ground
with brake pedal depressed
(Should be battery voltage
present)
Open circuit or poor connector
contact between stoplight
switch (or brake switch) and
stoplight NG OK

Reinstall or replace fuse No.
SBF-9 (50A)
or 1
C-108 - 4
C-107
Fuse No. C-18 (15A)


Fuse No. SBF-9 (50A, Fuse
and Relay box)
or 1
C-108 - 4
C-107
Fuse No. C-18 (15A)


Poor fuse contact or blown
NG
OK

ELECTRICAL-BODY AND CHASSIS 8A-167

3. High mounted stoplight does not light

Checkpoint Trouble Cause Countermeasure



Repair or replace the high
mounted stoplight

Continuity between 3
L-5 -
1
L-5


High mounted stoplight
malfunction
NG
Repair an open circuit or
connector contact between
3
L-5 - 8 H-6
Voltage between 1 L-5 -
ground with brake pedal
depressed
(Should be battery voltage
present)
Open circuit or poor connector
contact
NG OK

Repair grounding point contact

C-2


Grounding point
C-2


Poor grounding point contact
NG
OK

8A-168 ELECTRICAL-BODY AND CHASSIS
TURN SIGNAL LIGHT AND HAZARD WARNING LIGHT
1. Turn signal light does not light on both sides (RH and LH)

Checkpoint Trouble Cause Countermeasure



Replace the flasher unit

Flasher unit malfunction
NG

Repair or replace the
combination switch
Turn signal switch continuity
between connector
5
B-60 - 6 B-60 and
5
B-60 - 7 B-60 when
turn signal switch operates
Short circuit between
connector 3
B-61 - 1 B-61
when turn signal switch
operates with starter switch
in “ON” position (Turn
signal light should be ON)

Poor switch point contact or
faulty switch
NG OK

Reinstall or replace fuse No.
EB-16 (10A)

Fuse No. EB-16 (10A, Fuse
box)

Poor fuse contact or blown
fuse
NG
OK OK

Repair open circuit or
connector contact
Continuity between
connector 2
B-61 -ground
(Should be continuity)


Open circuit or poor connector
contact
NG

ELECTRICAL-BODY AND CHASSIS 8A-169
2. Turn signal light does not light on one side (RH or LH)

Checkpoint Trouble Cause Countermeasure



Repair open circuit or
connector contact

Open circuit or poor connector
contact
NG
(LH)
Continuity between
3
C-25 - 6 B-60 (FRT),
1
C-35 - 6 B-60 (SIDE)
1
F-6 - 6 B-60 (RR)
(RH)
Continuity between
3
C-18 - 7 B-60 (FRT),
1
C-1 - 7 B-60 (SIDE)
1
F-5 - 7 B-60 (RR)

Repair or replace the
combination switch

Turn signal switch continuity

Poor switch point contact or
faulty switch
NG
OK OK

Repair open circuit or
connector contact

Open circuit or poor connector
contact
NG



3. Hazard warning light does not light



Repair or replace the hazard
SW.

Hazard SW. malfunction
NG
Voltage between 5 B-16 -
ground (Should be battery
voltage present)

Hazard SW. continuity


Reinstall or replace the fuse
No. EB-16 (10A)

Fuse No. EB-16 (10A, Relay
and fuse box)

Poor fuse contact or blown
fuse
NG
OK OK

Repair open circuit or
connector contact
Open circuit or poor
connector contact between
fuse No. EB-16 (10A) -
5
B-16 NG



4. Flashing rate too fast (One side)

Replace the bulb or repair
open circuitInspect bulbBurned out bulb NG

8A-170 ELECTRICAL-BODY AND CHASSIS
BACKUP LIGHT
1. Backup light does not light on one side (RH or LH)

Checkpoint Trouble Cause Countermeasure

Repair grounding point contactPoor ground contact NGGrounding point
Replace the bulb or repair
connector contactBackup light bulb continuityBurned out bulb or poor
connector contact NG
OK



2. Backup light does not light on both sides



Repair or replace the switch

Poor switch point contact of
faulty switch
NG
Voltage between 5 F-6
(5
F-5 ) - ground with
starter switch ON and shift
lever into reverse position
(Should be battery voltage
present)

Back up light switch (mode
switch) continuity


Reinstall or replace fuse No.
C-4 (15A)

Fuse No. C-4 (15A, Fuse box)

Poor fuse contact or blown
fuse
NG
OK OK

Repair open circuit or
connector contact

Open circuit or poor connector
contact
NG

ELECTRICAL-BODY AND CHASSIS 8A-171
HORN
1. Both sides of horn do not sound

Checkpoint Trouble Cause Countermeasure



Repair the grounding point

Poor ground contact
NG

Horn relay


Grounding point


Reinstall or replace fuse No.
EB-15 (10A)

Fuse No EB-15 (10A, Relay
and fuse box)

Poor fuse contact or blown
fuse
NG
OK OK

Reinstall or replace the horn
relay

Poor relay contact or faulty
horn relay
NG
Voltage between connector
3
X-3 - ground or 1 X-3
- ground (Should be battery
voltage present) OK

Repair open circuit or
reconnect the connector
Open circuit or poor connector
contact between fuse No. EB-
15 (10A) and horn relay
NG

Remove steering pad and
steering wheel
OK

Horn switch continuity
OK
Repair or replace the horn
switch

Poor switch point contact or
faulty switch
NG
Continuity between
4
X-3 - 10 B-60
2
X-3 - 1 C-20 (1 C-21) OK

Repair open circuit or
connector contact

Open circuit or poor connector
contact
NG

8A-172 ELECTRICAL-BODY AND CHASSIS
2. One side of horn does not blow

Checkpoint Trouble Cause Countermeasure

Repair open circuit or
reconnect the connectorOpen circuit or poor connector
contact NG
Voltage between 1 C-20
(1 C-21) - ground with
horn switch depressed
(Should be battery voltage
present)
Replace the horn assemblyHorn continuity between
connectorsFaulty horn assembly NG
OK



3. Insufficient horn volume

Clfean and/or remove the
foreign materialStain foreign material in the
horn NGHorn
Recharge or replace the
batteryBattery conditionDischarged battery NG
OK