fuse ISUZU TF SERIES 2004 Service Manual

ELECTRICAL-BODY AND CHASSIS 8A-121
2. High or low beam does not light on both headlights

Checkpoint Trouble Cause Countermeasure


Repair or replace the
combination switch

Dimmer
passing switch
continuity

Poor switch contact or switch
faulty
NG

Repair open circuit or
connector contact
Voltage between
4
X-4 - ground and
4
B-60 - ground

Open circuit between
headlight and dimmer
passing
switch
NG OK



3. RH (or LH) high and low beam does not light



Replace the headlight bulb

Headlight connector continuity

Blown filament or air leakage
NG

Repair or replace the wire
and/or connector
Wiring continuity between
connector 3
C-19 - fuse No.
EB-7 or 3
C-26 fuse No.
EB-8

Open circuit and/or poor
connector contact
NG OK

Reinstall or replace fuse No.
EB-7 or No. EB-8
Fuse No. EB-7 (10A) or
No. EB-8 (10A) (Relay and
fuse box)
(No. EB-7 RH, No. EB-8: LH)
Poor installation or blown fuse
NG
OK



4. High or low beam does not light on one headlight (RH or LH)

Replace the headlight
assemblyHeadlight connector continuityBlown filament NG
Repair open circuit or
connector contactWiring continuity between
headlight and dimmer
passing
switchOpen circuit between
headlight and dimmer
passing
switch NG OK

8A-122 ELECTRICAL-BODY AND CHASSIS
5. Headlight does not go out

Checkpoint Trouble Cause Countermeasure


Replace the lighting relay
Lighting relay continuity
between connector 1
X-12
- 2
X-12 (Should be no
continuity)

Relay point fused
NG

Replay the combination switch
Lighting switch continuity
between connector 3
B-60
-1
B-60 when switch is
OFF(Should be no continuity)

point fused or faulty

NG
OK OK

Repair or replace the
combination switch
Dimmer
passing switch con-
tinuity between connector
3
B-60 - 1 B-60 when switch
is not operating
(Should be no continuity)

Switch point fused or faulty
NG
Repair short circuit
between 4
X-12 - 3 B-60
and 4
X-1 - 2 B-60
Check if headlight goes out
when connector
C-30 is
disconnected


Short circuit
NG OK



6. Insufficient headlight brightness



Replace the headlight bulb

Headlight bulb

Bulb filament faulty
NG

Repair the wiring
Dimmer
passing switch
Wire continuity between con-
nector 1
B-60 - C-36


Poor ground point contact
NG OK

Clean the light lens

Headlight lens

Lens dirty
NG
OK

8A-124 ELECTRICAL-BODY AND CHASSIS
TAIL LIGHT, LICENSE PLATE LIGHT, CLEARANCE LIGHT

1. All lights do not light

Checkpoint Trouble Cause Countermeasure



Repair or replace the
combination switch
Lighting switch continuity
between connector
2
B-60 - 1 B-60


Poor switch point or connector
contact
NG

Reinstall or replace the tail
relay

Tail relay


Poor relay contact or relay
faulty
NG OK

Reinstall or replace the fuse
No. EB-6

Fuse No. EB-6 (10A, Relay
and fuse box)

Poor fuse contact or blown
NG
OK



2. Tail light does not light


Replace the bulb or repair
connector contact

Tail light bulb continuity

Bulb burned out or poor
connector contact
NG

Repair open circuit or
connector contact
Continuity between connector
3
F-5 - 4 F-5 (RH)
or 3
F-6 - 4 F-6 (LH)


Open circuit or poor connector
contact
NG OK

ELECTRICAL-BODY AND CHASSIS 8A-125
TAIL LIGHT-LH, LICENSE PLATE LIGHT, CLEARANCE LIGHT

1. All lights do not light (EC-LHD)

Checkpoint Trouble Cause Countermeasure



Repair or replace the
combination switch
Lighting switch continuity
between connector
2
B-60 - 1 B-60


Poor switch point or connector
contact
NG

Reinstall or replace the tail
relay

Tail relay


Poor relay contact or relay
faulty
NG OK

Reinstall or replace the fuse
No. EB-6

Fuse No. EB-6 (10A, Relay
and fuse box)

Poor fuse contact or blown
NG
OK



2. Tail light does not light


Replace the bulb or repair
connector contact

Tail light bulb continuity

Bulb burned out or poor
connector contact
NG

Repair open circuit or
connector contact

Continuity between connector
or 3
F-6 - 4 F-6 (LH)

Open circuit or poor connector
contact
NG OK

8A-126 ELECTRICAL-BODY AND CHASSIS
TAIL LIGHT-RH

1. All lights do not light (EC-LHD)

Checkpoint Trouble Cause Countermeasure



Repair or replace the
combination switch
Lighting switch continuity
between connector
2
B-60 - 1 B-60


Poor switch point or connector
contact
NG

Reinstall or replace the tail
relay

Tail relay


Poor relay contact or relay
faulty
NG OK

Reinstall or replace the fuse
No. EB-6

Fuse No. EB-5 (10A, Relay
and fuse box)

Poor fuse contact or blown
NG
OK



2. Tail light does not light


Replace the bulb or repair
connector contact

Tail light bulb continuity

Bulb burned out or poor
connector contact
NG

Repair open circuit or
connector contact

Continuity between connector
3
F-5 - 4 F-5 (RH)


Open circuit or poor connector
contact
NG OK

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

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