2004 ISUZU TF SERIES switch

ELECTRICAL-BODY AND CHASSIS 8A-11
SYMBOLS AND ABBREVIATIONS
SYMBOLS
Symbol Meaning of Symbol Symbol Meaning of Symbol


Fuse
Bulb



Fusible link
Double filament bulb



Fusible link wire
Motor


Switch
Variable resistor Rheostat


Switch
Coil (inductor), solenoid,
magnetic valve


Switch (Normal close type)





Contact wiring
Relay


Battery




Diode
Connector


Electronic Parts
Light emitting diode



Resistor
Reed switch


Speaker
Condenser



Buzzer
Horn


Circuit breaker
Vacuum switching valve

8A-12 ELECTRICAL-BODY AND CHASSIS
ABBREVIATIONS
Abbreviation Meaning of abbreviation Abbreviation Meaning of abbreviation
A Ampere (S) LH Left hand
ABS Anti-lock brake system LWB Long wheel base
ASM Assembly MPI Multipart fuel injection
AC Alternating current M/T Manual transmission
A/C Air conditioner QOS Quick On Start system
ACC Accessories RH Right hand
CARB Carburetor RR Rear
C/B Circuit breaker RWAL Rear wheel anti-lock brake system
CSD Cold start device SRS Supplemental restraint system
DIS Direct ignition system ST Start
EBCM Electronic brake control module STD Standard
ECGI Electronic control gasoline injection SW Switch
ECM Engine control module SWB Short wheel base
ECU Electronic control unit TCM Transmission control module
EFE Early fuel evaporation V Volt
42 Two-wheel drive VSV Vacuum switching valve
44 Four-wheel drive W Watt (S)
FL Fusible link WOT Wide open throttle
FRT Front W/ With
H/L Headlight W/O Without
IC Integrated circuit
IG Ignition
kW Kilowatt

8A-16 ELECTRICAL-BODY AND CHASSIS


RELAY
Battery and load location may require that a switch be placed
some distance from either component.
This means a longer wire and a higher voltage drop
1. The
installation of a relay between the battery and the load reduces
the voltage drop
2.
Because the switch controls the relay, amperage through the
switch can be reduced.


Relay Specifications and Configurations
Name/
Color Rated
voltage/ Coil
resistance Internal circuit Name/
color Rated
Voltage/Coil
resistance Internal circuit
1T
(MICRO
ISO)
/Black 12V
Approx. 92
Minimum
operating
voltage: 7V at
20C (77F)

1M (MINI
ISO)
/Black 12V Approx.
94 Minimum
operating
voltage: 7V at
20C (77F)

1M
(MICRO
ISO)
/Black 12V
Approx. 132-3
 Minimum
operating
voltage: 7V at
20C (77F)

1M
(power)/
Black 12V Approx.
94 Minimum
operating
voltage: 7V at
20C (77F)

* Relay contact shown in the wiring diagram indicates condition before actuation.

8A-88 ELECTRICAL-BODY AND CHASSIS
REMOVAL AND INSTALLATION

This illustration is based on RHD model
STARTER SWITCH
Removal
1. Steering Lock Assembly

Refer to Section 3B" STEERING COLUMN" for steering
lock assembly removal steps.
2. Starter Switch




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


INSPECTION AND REPAIR


STARTER SWITCH
Switch Connections
Terminal No.

Starter
switch key
position B-62
2
(B2)B-62
4
(ACC)B-62
1
(IG2) B-63
1
(ST) B-63
3
(B1)B-62
3
(IG1)
Removed

OFF
ACC Inserted
ON
START
LOCK

825R300046

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

8A-120 ELECTRICAL-BODY AND CHASSIS
TROUBLE SHOOTING
HEADLIGHT
1. Both the headlights (high and low beam) do not light

Checkpoint Trouble Cause Countermeasure


Repair the wiring

Poor ground point contact
NG

Repair open circuit or
connector contact


Repair open circuit


Repair or replace the
combination switch


Voltage between 1
B-60 -
ground


Open circuit between lighting
relay and lighting switch

Open circuit between battery
positive terminal and lighting
relay

Combination switch continuity

Poor switch contact or sw
faulty

Voltage between
5
X-12 - ground and
2
X-12 - ground


Reinstall or replace the
lighting relay

Lighting relay

Poor relay contact or relay
faulty

NG NG NG NG OK
OK
OK OK

Ground point contact (C-36)


Repair open circuit
Wiring continuity between

B-60 - C-36


Open circuit
NG OK

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

ELECTRICAL-BODY AND CHASSIS 8A-123
7. Passing light does not function when dimmer switch is operated

Checkpoint Trouble Cause Countermeasure


Repair or replace the dimmer
switch

Dimmer switch

Poor switch point contact
NG

Repair open circuit between
4
X-12 - 3 B-60

Voltage between
3
B-60 - ground (Should
be battery voltage present)


Open circuit
NG OK



8. Headlight beam does not change when dimmer switch is operated

Repair or replace the dimmer
switchDimmer switchLoose beam lever or foreign
material in switch NG