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GM Vehicle Care/Appearance Materials
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Vehicle Identification Number (VIN)
This is the legal identifier for your vehicle. It appears on
a plate in the front corner of the instrument panel, on the
driver's side. You can see it if you look through the
windshield from outside your vehicle. The VIN also
appears on the Vehicle Certification and Service Parts
labels and the certificates of title and registration.
Engine Identification
The 8th character in your VIN is the engine code. This
code will help you identify your engine, specifications
and replacement parts.
Service Statement
One of these statements is on your GVW Rating label.
Here is what each one means.
TRUCK SERVICE
-- A vehicle made to carry
property or special equipment. It is made for uniform
frame loading. That includes using the vehicle to pull a
full trailer.
TRUCK
-TRACTOR -- A vehicle made to draw other
vehicles. It's made to carry part of the load of the trailer.
It is made for point frame loading, usually for a
semi
-trailer (ªfifth wheelº).
MAX. VERT. CG
-- The highest allowable vertical
center of gravity, at the highest allowable GVWR. It's
measured from level ground in inches.
TRUCK
-CANADA -- A vehicle first sold in Canada
with a non
-school bus application, or cab models with
regular production option RQ2 (ªtruck serviceº).
TRACTOR
-CANADA -- A cab model with regular
production option RQ3 (ªtruck
-tractor serviceº).
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Service Parts Identification Label
You'll find this label in a location determined by the
body manufacturer. It's very helpful if you ever need to
order parts. On this label is:
your VIN,
the model designation,
paint information and
a list of all production options and special
equipment.
Be sure that this label is not removed from the vehicle.
Electrical System
Add-On Electrical Equipment
NOTICE:
Don't add anything electrical to your vehicle
unless you check with your dealer first. Some
electrical equipment can damage your vehicle
and the damage wouldn't be covered by your
warranty. Some add
-on electrical equipment
can keep other components from working as
they should.
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6-78 Headlamp Wiring
The headlamp wiring is protected by a circuit breaker in
the light switch. An electrical overload will cause the
lights to go on and off, or in some cases to remain off.
If this happens, have your headlamp wiring checked
right away.
Windshield Wiper Fuses
The windshield wiper motor is protected by a circuit
breaker inside the motor and a circuit breaker or fuse in
the fuse block. If the motor overheats, the wipers will
stop until the motor cools. If the overload is caused by
an electrical problem, be sure to get it fixed.
Fusible Links
A fusible link is a short piece of wire several gauge sizes
smaller than the circuit it protects. It will melt in an
overload situation, opening the circuit.
Your starter and other circuits have these fusible links.
The size is printed on the insulation. If the insulation is
burned beyond recognition, consult your GM dealer for
the proper size. Replace a fusible link with one of the
same size and insulation type. Fusible link insulation is a
special purpose high
-temperature material.
The hydraulic brake booster motor feed circuit and
starter circuit are protected by a fusible link. Vehicles
with a diesel engine have a fusible link for the intake
heater feed circuit.
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6-79 Power Windows and Other Power Options
Circuit breakers in the fuse panel protect the power
windows and other power accessories. When the current
load is too heavy, the circuit breaker opens. This
protects the circuit until the current load returns to
normal or the problem is fixed.
Fuses and Circuit Breakers
The wiring circuits in your vehicle are protected from
short circuits by a combination of fuses, circuit breakers,
maxi
-fuses and fusible links. This greatly reduces the
chance of a fire caused by an electrical problem. There
may be a fuse taped to the wiring harness near the
hydraulic brake booster.
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Instrument Panel Fuse Block
There are two instrument panel fuse blocks located behind the instrument panel on the passenger's side of the vehicle.
Be sure to replace fuses with fuses of the same rating. Do not use fuses of higher amperage than those indicated on
the fuse block.
Fuse Block 1
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Fuse Usage
RH PARK LP Right
-hand Parking Lamps
LH PARK LP Left
-hand Parking Lamps
RADIO U Radio
PWR WINDOW Power Windows
BRAKE ISO Brake Warning Lamp
SPARE Spare Fuse
L
-RR TRUCK Left Rear Trailer Wiring
SPARE Spare Fuse
SPARE Spare Fuse
SPARE Spare Fuse
R
-RR TRUCK Right Rear Trailer Wiring
SPARE Spare FuseRelay Usage
BRAKE LAMP C4/C5 Brake Lamps, C6/C7/C8
Tractor/Trailer Wiring
IGN 4 Ignition
MARKER LP Sidemarker and Clearance Lamps
HTD FUEL LB7/LG4 Heated Fuel
AIR HTR LG4 Air Heater
ECU
MAINTAINLG4 Electronic Control Unit
DRL Daytime Running Lamps
CHMSL ISO Center High Mounted Stop Lamp
HTD MIRR Heated Mirrors
R-TRN TLR Right Trailer Turn Signal
L
-TRN TLR Left Trailer Turn Signal
SPARE Spare Relay
SPARE Spare Relay
SPARE Spare Relay
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Fuse Block 2
Circuit Breaker Usage
1 Stoplamps
2 Center High Mounted Stop Lamp
3 Parking Lamps
4 Powertrain Control Module
5 Auxiliary Wiring
6 Heater/Air ConditioningCircuit Breaker Usage
7 Hazard Warning Flashers
8 Power Post
9 Courtesy Lamps
10 Warning Lights, Gages
and Indicators
11 Crank
12 Rear Axle
13 Trailer Turn Signals/Hazard
Warning Flashers
14 Radio/Chime
15 Daytime Running Lamps
16 Air Bag System
17 Exterior/Interior Lamps
18 Parking Brake
19 Accessory Power
20 Ignition
21 Sidemarker Lamps
22 Turn Signal/Backup Lamps
23 Transmission
24 Chassis
A Spare
B Spare