2002 GMC ENVOY headlamp

6-45
Each new wheel should have the same load-carrying
capacity, diameter, width, offset and be mounted the
same way as the one it replaces.
If you need to replace any of your wheels, wheel bolts
or wheel nuts, replace them only with new GM original
equipment parts. This way, you will be sure to have the
right wheel, wheel bolts and wheel nuts for your vehicle.
CAUTION:
Using the wrong replacement wheels, wheel bolts
or wheel nuts on your vehicle can be dangerous.
It could affect the braking and handling of your
vehicle, make your tires lose air and make
you lose control. You could have a collision in
which you or others could be injured. Always
use the correct wheel, wheel bolts and wheel nuts
for replacement.
NOTICE:
The wrong wheel can also cause problems with
bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper
height, vehicle ground clearance and tire or tire
chain clearance to the body and chassis.
See ªChanging a Flat Tireº in the Index for
more information.
Used Replacement Wheels
CAUTION:
Putting a used wheel on your vehicle is
dangerous. You can't know how it's been used or
how far it's been driven. It could fail suddenly
and cause a crash. If you have to replace a wheel,
use a new GM original equipment wheel.

6-56
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.
Your vehicle has an air bag system. Before attempting to
add anything electrical to your vehicle, see ªServicing
Your Air Bag
-Equipped Vehicleº in the Index.
Headlamps
The headlamp wiring is protected by four fuses. An
electrical overload will cause a lamp to go on and 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 or ice, the wiper will stop until the motor cools. If
the overload is caused by some electrical problem, 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.

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Mini Fuses Usage
1 ECAS
2 Passenger's Side
High
-Beam Headlamp
3 Passenger's Side
Low
-Beam Headlamp
4 Back
-Up Trailer Lamps
5 Driver's Side
High
-Beam Headlamp
6 Driver's Side
Low
-Beam Headlamp
7 WASH
8ATC
9 Windshield Wipers
10 Powertrain Control Module B
11 Fog Lamps
12 ST/LP
13 Cigarette Lighter
14 COILSMini Fuses Usage
15 RIDE
16 TBD
-- Ignition 1
17 Crank
18 Air Bag
19 ELEK Brake
20 Cooling Fan
21 Horn
22 Ignition E
23 ETC
24 Instrument Panel Cluster,
Driver Information Center
25 Automatic Shift Lock
Control System
26 ENG 1
27 Back
-Up
28 Powertrain Control Module 1
29 Oxygen Sensor

6-60
Mini Fuses Usage
30 Air Conditioning
31 TBC
50 Passenger's Side Trailer TRN
51 Driver's Side Trailer TRN
52 Hazard Flashers
J
-Case Fuses Usage
32 Trailer
33 Anti
-Lock Brakes (ABS)
34 Ignition A
35 Blower Motor
36 Ignition B
Micro Relays Usage
37 Headlamp Washer
38 Rear Window Washer
39 Fog LampsMicro Relays Usage
40 Horn
41 Fuel Pump
42 Windshield Wipers/Washer
43 High
-Beam Headlamp
44 Air Conditioning
Solid State
RelaysUsage
45 Cooling Fan
46 HDM
Mini Relay Usage
47 Starter
Miscellaneous Usage
48 Instrument Panel Battery
49 Fuse Puller

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Fuse Usage
35 Blank
36 HVAC B
37 Front Parking Lamps
38 Left Turn Signal
39 HVAC 1
40 TBC 4
41 Radio
42 TR PARK
43 Right Turn Signal
44 HVAC
45 Rear Fog Lamps
46 Auxiliary Power 1
47 Ignition 0
48 Four
-Wheel Drive
49 Blank
50 TBC IG
51 Brakes
52 TBC RUN
Replacement Bulbs
Lamps Number
Halogen Headlamps
Low Beam 9006 HB4. . . . . . . . . . . . . . . . . . . . . . . .
High Beam 9005 HB3. . . . . . . . . . . . . . . . . . . . . . .
Front Sidemarker Lamps 194. . . . . . . . . . . . . . . . . . .
Front Turn Signal Lamps 3457. . . . . . . . . . . . . . . . . .
Tail and Stoplamps 3057. . . . . . . . . . . . . . . . . . . . . . .
Rear Turn Signal Lamps 3057. . . . . . . . . . . . . . . . . .
For any bulb not listed here contact your dealer.
Capacities and Specifications
Engine Specifications
Engine Description ªVORTECº 4200. . . . . . . . . . . .
Type L6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VIN Code S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Firing Order 1
-5-3-6-2-4 . . . . . . . . . . . . . . . . . . . . . .
Spark Plug Gap 0.050 inches (1.25 mm). . . . . . . . . .