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-
/! CAUTION:
You can be injured and your vehicle could be
damaged
if you try to do service work on a
vehicle without knowing enough about it.
Be sure you have sufficient knowledge,
experience, the proper replacement parts and tools before you attempt
any vehicle
maintenance task.
Be sure to use the proper nuts, bolts and
other fasteners. “English” and “metric”
fasteners can be easily confused. If you use
the wrong fasteners, parts can later break
or fall off.
You could be hurt.
Adding Equipment to the Outside of
Your Vehicle
Things you might add to the outside of your vehicle can
affect the airflow around
it. This may cause wind noise
and affect windshield washer performance. Check
with
your dealer before adding equipment to the outside of
your vehicle.
Fuel (Gasoline Engine)
If your vehicle has a diesel engine, see “Diesel Fuel
Requirements and Fuel System”
in the Diesel Engine
Supplement. For vehicles with gasoline engines, please.
read this.
Use regular unleaded gasoline rated at
87 octane or higher.
At
a minimum, it should meet specifications ASTM D48 14
in the United States and CGSB 3.5-M93 in Canada.
Improved gasoline specifications have been developed
by
the American Automobile Manufxturers Association
(AAMA) for better vehicle performance and engine
protection. Gasolines meeting the
AAMA specification
could provide improved chiveability and emission control
system protection compared to other gasolines.
6-3
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“VORTEC” 4300,5000,5700 Engine, “VORTEC” 5700 engine shown, locations for other engines similar.
When you lift
up the hood you’ll see:
A. Battery
G. Automatic Transmission L. Clutch Fluid Reservoir
B. Air Cleaner
Dipstick
(If Equipped) (If Equipped)
C. Radiator Cap H. Fan M. Windshield Washer Fluid
D. Coolant Recovery Tank I. Power Steering Fluid Reservoir Reservoir
E. Air Filter Restriction Indicator J. Engine Oil Fill N. FuseRelay Center
F. Engine Oil Dipstick K. Brake Fluid Reservoir
6-11
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“VORTEC” 7400 Engine
A. Battery
B. Coolant Recovery Tank
C. Air Cleaner
D. Radiator Cap
E. Air Filter Restriction Indicator
F. Engine Oil Dipstick
G. Automatic Transmission L. Clutch Fluid Reservoir
Dipstick (If Equipped)
(If Equipped)
H. Engine Oil Fill M. Windshield Washer
I. Fan Fluid Reservoir
J. Power Steering Fluid Reservoir N. Fusemelay Center
K. Brake Fluid Reservoir
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Headlamps Fuses and Circuit Breakers
The headlamp wiring is protected by an internal circuit
breaker. An electrical overload will cause
the lamps
to go on and off, or
in some cases to remain off. If
this happens, have your headlamp wiring checked
right away.
Windshield Wipers
The windshield wiper motor is protected by a circuit
breaker and
a fuse. If the motor overheats due to heavy
snow, etc., the wiper will stop
until the motor cools. If
the overload is caused by some electrical problem and
not snow, etc., be sure to get it fixed.
Power Windows and Other Power Options
Circuit breakers protect the power windows and other
power accessories. When the current load is too heavy,
the circuit breaker opens and closes, protecting the
circuit
until the problem is fixed or goes away. The wiring circuits
in your vehicle are protected from
short circuits by
a combination of fuses, circuit breakers
and fusible thermal links.
This greatly reduces the
chance
of fires caused by electrical problems.
Look at the silver-colored band inside the fuse. If the
band is broken or melted, replace the fuse. Be sure you
replace
a bad fuse with a new one of the identical size
and rating.
If you ever have
a problem on the road and don’t have a
spare fuse, you can “borrow” one that has the same
amperage. Just pick some feature
of your vehicle that
you can get along without
-- like the radio or cigarette
lighter
-- and use its fuse, if it is the correct amperage.
Replace
it as soon as you can.
6-7 1
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Instrument Panel Fuse Block
The fuse block access door
is on the driver’s side edge
of the instrument panel. Pull
off the cover to access the
fuse block.
You can remove
fuses with a fuse extractor. The fuse
extractor
is mounted to the fuse block access door. To
remove fuses if you don’t have a fuse extractor, hold the
end
of the fuse between your thumb and index finger
and
pull straight out.
You may have spare fuses located behind the fuse block
access door. These can be used to replace a bad fuse.
However, make
sure it is of the correct amperage.
J
D
13
ug
7 I
FuseKircuit
Breaker
1
2
Usage
Stop/TCC Switch, Buzzer,
CHMSL, Hazard Lamps,
S toplamps
Transfer
Case
6-72
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FuseKircuit Breaker
3
4
Usage
Courtesy Lamps, Cargo Lamp,
Glove Box Lamp, Dome/Reading
Lamps, Vanity Mirrors,
Power Mirrors
Instrument Cluster, DRL Relay,
Lamp Switch, Keyless Entry,
Low Coolant Module, Illuminated Entry Module,
DRAC (Diesel Engine)
Not Used
Cruise Control
Auxiliary Power Outlet
Crank
License Lamp, Parking Lamps,
Taillamps,
Roof Marker Lamps,
Tailgate Lamps, Front
Sidemarkers, Fog Lamp Relay,
Door Switch Illumination,
Fender Lamps, Headlamp Switch Illumination
FuseKircuit
Breaker
10
11
12
13
14
15
I6
17
18
19
Usage
Air Bag System
Wiper Motor, Washer Pump
A/C,
A/C Blower,
High Blower Relay
Power
Amp, Cigarette Lighter,
Door Lock Relay,
Power Lumbar Seat
4WD Indicator, Cluster, Comfort
Controls, Instrument Switches,
Radio Illumination,
Chime Module
DRL Relay,
Fog Lamp Relay
Front and Rear Turn Signals,
Back-up Lamps, BTSl Solenoid
Radio (Ignition)
4WAL/VCM, ABS. Cruise Control
Radio (Batterv)
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Fuse/Circuit Breaker Usage
20
21
22
23
24
A
B
PRNDL, Automatic Transmission,
Speedometer, Check Gages
Warning Light
Security/Steering
Not Used
Not Used
Front Axle,
4WD Indicator Lamp,
TP2 Relay (Gasoline Engine)
Power Door Lock, Six-Way Power Seat, Keyless Entry Module
Power Windows
Underhood Fuse/Relay Center
The underhood fusehelay center is located in the rear of
the engine compartment near the brake fluid reservoir.
Move the retainer clips
for the cover to access the
fuse block.
You can remove fuses with a fuse extractor. The fuse
extractor
is mounted to the interior fuse block. TO
remove fuses
if you don’t have a fuse extractor, hold the
end of the fuse between your thumb and index finger
and pull straight out.
6-74
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STARTER RELAY
[-I
[-I
[T)
I BLOWER
n STOPiHAZ
Name
ECM-B RR DEFOG
IGN-E
FUEL
SOL
GLOW PLUG
Usage
Horn, Underhood Lamps
Auxiliary Fan
Injectors, PCM/VCM
Not Used
Air Conditioning
Not Used
Ignition Switch, EGR, Canister
Purge, EVRV Idle Coast Solenoid,
Heated
02, Fuel Heater
(Diesel Engine), Water Sensor
(Diesel Engine)
HTD ST-RR Not Used
LIGHTING Headlamp and Panel Dimmer
BATT Battery, Fuse Block Busbar
IGN-A Ignition Switch
IGN-B Ignition Switch Switch,
Fog and Courtesy Fuses
ABS Anti-Lock Brake Module
BLOWER High Blower Relay
STOP/HAZ Stoplamps
HEATED SEATS Not Used
6-75
Usage
Fuel Pump, PCM/VCM
Rear Window Defogger
Auxiliary Fan Relay Coi
il, AIC
Compressor Relay, Hot Fuel
Module, Dual Tanks
Fuel Solenoid (Diesel Engine)
Glow Plugs (Diesel Engine)
Name
HORN
AUX FAN
ECM- 1
HTD ST-FR
AIC HTD MIR
ENG-
1
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