ISUZU TF SERIES 2004 Workshop Manual

ELECTRICAL-BODY AND CHASSIS 8A-3
PAGE
Power Window ........................................................................................................... 8A- 310
Audio, Clock and Cigarette Lighter .......................................................................... 8A- 329
Power Door Mirror ...................................................................................................... 8A- 337
Rear Defogger ............................................................................................................ 8A- 349
SRS-Air Bag ................................................................................................................ 8A- 358
Transfer Case Control Module .................................................................................. 8A- 361
Anti-Lock Brake System ............................................................................................ 8A- 373
Immobilizer ................................................................................................................. 8A- 376
Keyless Entry ............................................................................................................. 8A- 385
Anti Theft ....................................................................................................................8A- 400
Auto Cruise ................................................................................................................. 8A- 412
Trailer Hitch ................................................................................................................ 8A- 415
Connector List ................................................................................................................8A- 418

8A-4 ELECTRICAL-BODY AND CHASSIS
GENERAL INFORMATION
The body and chassis electrical system operates on a twelve volt power supply with negative ground polarity.
The main harness consists of the engine harness, the instrument harness, the body harness, and the chassis
harness.
The harnesses use a split corrugated tube to protect the wires from the elements.
Wire size is determined by current flow, circuit length, and voltage drop.
All wires have color-coded insulation.
Wire color-codes are shown in the circuit diagrams.
This makes it easier to trace circuits and to make the proper connections.
Each circuit consists of the following:
1. Power source - The battery and the alternator
2. Wires - To carry electrical current through the circuit
3. Fuses - To protect the circuit against current overload
4. Relays - To protect voltage drop between the battery and the circuit parts and to protect the switch points against
burning
5. Switches - To open and close the circuit
6. Load - Any device, such as a light or motor, which converts the electrical current into useful work
7. Ground - To allow the current to flow back to the power source

ELECTRICAL-BODY AND CHASSIS 8A-5
NOTES FOR WORKING ON ELECTRICAL ITEMS
Battery

BATTERY CABLE
Disconnecting the Battery Cable
1. All switches should be "OFF" position.
2. Disconnect the battery ground cable.
3. Disconnect the battery positive cable.
CAUTION:
It is important that the battery ground cable be
disconnected first.
Disconnecting the battery positive cable first can result in
a short circuit.














Connecting the Battery Cable
Follow the disconnecting procedure in the reverse order to
connect the battery cables.
CAUTION:
Clean the battery terminal and apply light coat of grease to
prevent terminal corrosion.




CONNECTOR HANDLING
Disconnecting the Connectors
Some connectors have a tang lock to hold the connectors
together during vehicle operation.
Some tang locks are released by pulling them towards you
1.
Other tang locks are released by pressing them forward
2.
Determine which type of tang lock is on the connector being
handled.



Firmly grasp both sides (male and female) of the connector.
Release the tang lock and carefully pull the two halves of the
connector apart.
Never pull on the wires to separate the connectors.
This will result in wire breakage.

8A-6 ELECTRICAL-BODY AND CHASSIS


Connecting the Connectors
Firmly grasp both sides (male and female) of the connector.
Be sure that the connector pins and pin holes match.
Be sure that both sides of the connector are aligned with each
other.
Firmly but carefully push the two sides of the connector
together until a distinct click is heard.


Connector Inspection
Use a circuit tester to check the connector for continuity.
Insert the test probes from the connector wire side.



CAUTION
Never insert the circuit tester test probes into the
connector open side to test the continuity.
Broken or open connector terminals will result.



Waterproof Connector Inspection
It is not possible to insert the test probes into the connector
wire side of a waterproof connector.
Use one side of a connector
1 with its wires cut to make the
test.
Connect the test connector to the connector
2 to be tested.
Connect the test probes to the cut wires to check the connecto
r
continuity.



Connector Pin Removal
Connector Housing Tang Lock Type
1. Insert a slender shaft 3into the connector housing open
end
4.
2. Push the tang lock
5up (in the direction of the arrow in the
illustration).
Pull the wire
6 with pin 7free from the wire side of the
connector.

ELECTRICAL-BODY AND CHASSIS 8A-7


Pin Tang Lock Type
1. Insert a slender shaft 3 into the connector housing open
end
4.
2. Push the tang lock
8flat (toward the wire side of the
connector).
Pull the wire
6 with pin 7free from the wire side of the
connector.



Connector Pin Insertion
1. Check that the tang lock 8 is fully up.
2. Insert the pin
7 from the connector wire side 9.
Push the pin in until the tang lock closes firmly.
3. Gently pull on the wires
6to make sure that connector pin
is firmly set in place.



Fuse Replacement
The replacement fuse must have the same amperage
specification as the original fuse.
Never replace a burn out fuse with a fuse of a different
amperage specification.
Doing so can result in an electrical fire or other serious circuit
damage.



Parts Handling
Be careful for parts handling and any part should not be
dropped or thrown, otherwise short circuit or disorder may
result.



Wiring Harness
1. When assembling the parts, be careful not to bite or wedge
the wiring harness.
2. All electrical connections must be kept clean and tight.

8A-8 ELECTRICAL-BODY AND CHASSIS


3. Use a grommet or guard tube to protect the wiring harness
from contacting a sharp edge or surface.



4. Position the wiring harness with enough clearance from the
other parts and guard the wiring harness with a vinyl tube to
avoid direct contact.



5. The wiring harness between engine and chassis should be
long enough to prevent chafing or damage due to various
vibrations.

ELECTRICAL-BODY AND CHASSIS 8A-9

SPLICING WIRE
Open the Harness
If the harness is taped, remove the tape.
To avoid wire insulation damage, use a sewing "seam ripper"
(available from sewing supply stores) to cut open the harness.
If the harness has a black plastic conduit, simply pull out the
desired wire.
Cut the wire
Begin by cutting as little wire off the harness as possible.
You may need the extra length of wire later if you decide to cut
more wire off to change the location of a splice.
You may have to adjust splice locations to make certain that
each splice is at least 1-1/2" (40 mm) away from other splices,
harness branches, or connectors.
Strip the insulation
When replacing a wire, use a wire of the same size as the
original wire.
Check the stripped wire for nicks or cut strands.
If the wire is damaged, repeat the procedure on a new section
of wire.
The two stripped wire ends should be equal in length.



Crimp the Wires
Select the proper clip to secure the splice.
To determine the proper clip size for the wire being spliced,
follow the directions included with your clips.
Select the correct anvil on the crimper.
(On most crimpers your choice is limited to either a small or
large anvil.)
Overlap the two stripped wire ends and hold them between
your thumb and forefinger.
Then, enter the splice clip under the stripped wires and hold it
in place.




Open the crimping tool to its full width and rest one handle
on a firm flat surface.

Center the back of the splice clip on the proper anvil and
close the crimping tool to the point where the back of the
splice clip touches the wings of the clip.

Make sure that the clip and wires are still in the correc
t
position. Then, apply pressure until the crimping tool closes.



Before crimping the ends of the clip, be sure that:

The wires extend beyond the clip in each direction.

No strands of wire are cut loose.

No insulation is caught under the clip.
Crimp the splice again, once on each end.
Do not let the crimping tool extend beyond the edge of the clip
or you may damage or nick the wires.

8A-10 ELECTRICAL-BODY AND CHASSIS



Solder
Apply 60/40 rosin core solder to the opening in the back of the
clip.
Follow the manufacturer's instructions for the solder equipment
you are using.



Tape the Splice
Center and roll the splicing tape.
The tape should cover the entire splice.
Roll on enough tape to duplicate the thickness of the insulation
on the existing wires.
Do not flag the tape.
Flagged tape may not provide enough insulation, and the
flagged ends will tangle with the other wires in the harness.



If the wire does not belong in a conduit or other harness
covering, tape the wire again.
Use a winding motion to cover the first piece of tape.

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