2001 GMC ENVOY headlamp

6-36 Headlamps
One-Piece Composite Headlamp System
1. Open the hood.
2. Remove the black retainer clips by lifting up.
3. Pull the headlamp assembly out.
4. Unplug the electrical connector.
5. Turn the bulb/socket assembly counterclockwise to
remove it.
6. Put the new bulb/socket assembly into the headlamp
assembly and turn it clockwise until it is tight.
7. Plug in the electrical connector.
8. Put the headlamp assembly back into the vehicle.
9. Install the two retaining clips.
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6-37
Tw o-Piece Composite Headlamp System
1. Open the hood.
2. Remove the black retainer clips by lifting up.
3. Pull the headlamp assembly out.
4. Unplug the electrical connector.
5. Turn the bulb/socket assembly counterclockwise to
remove it.
6. Put the new bulb/socket assembly into the headlamp
assembly and turn it clockwise until it is tight.
7. Plug in the electrical connector.
8. Put the headlamp assembly back into the vehicle.
9. Install the two retaining clips.
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6-38
Composite High-Beam Headlamp System (Vehicles
with High Intensity Discharge Lighting Only)
1. Open the hood.
2. Remove the black retainer clips by lifting up.
3. Pull the headlamp assembly out.
4. Unplug the electrical connector.
5. Turn the bulb/socket assembly counterclockwise to
remove it.
6. Put the new bulb/socket assembly into the headlamp
assembly and turn it clockwise until it is tight.
7. Plug in the electrical connector.
8. Put the headlamp assembly back into the vehicle.
9. Install the two retaining clips.
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6-39 One-Piece Front Turn Signal
Lamp Assembly
1. Remove the headlamp assembly as shown under
ªOne
-Piece Composite Headlamp Systemº earlier
in this section.
2. Twist the bulb socket to
remove it from the
headlamp assembly.3. Pull the bulb straight out to remove it from
the socket.
4. Push the new bulb into the socket until it snaps
into place.
5. Put the bulb socket into the lamp assembly and turn
it clockwise until it is tight.
6. Put the headlamp assembly back into the vehicle.
Install the two retaining clips.
7. Install the two retaining clips.
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6-40 Two-Piece Front Turn Signal
Lamp Assembly
1. Remove the headlamp assembly as shown under
ªTwo
-Piece Composite Headlamp Systemº earlier
in this section.
2. Locate the locking tabs
on the assembly.
Squeeze the tabs
together and push that
end of the assembly out
while holding the tabs.
The assembly will
swing out.
3. Unplug the electrical connector.
4. Turn the harness bulb socket counterclockwise to
remove it.
5. Pull the bulb straight out to remove it from the socket.
6. Push the new bulb into the socket until it snaps into place.
7. Reinstall the harness bulb socket with the new bulb
into the headlamp assembly and turn it clockwise
until it is tight.
8. To reinstall the assembly, snap the outboard end of
the lamp assembly back into the vehicle. Then swing
the assembly in and snap it into place.
9. Install the two retaining clips.
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6-51
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 an accident. If you have to replace a
wheel, use a new GM original equipment wheel.
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6-63
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 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 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.
Fuses and Circuit Breakers
The wiring circuits in your vehicle are protected from
short circuits by a combination of fuses and circuit
breakers. 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.
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6-65
Fuse/Circuit
BreakerUsage
3 Cruise Control Module and
Switch, Body Control Module,
Heated Seats
4 Gages, Body Control Module,
Instrument Panel Cluster
5 Parking Lamps, Power Window
Switch, Body Control Module,
Ashtray Lamp
6 Steering Wheel Radio Controls
7 Headlamps Switch, Body Control
Module, Headlamp Relay
8 Courtesy Lamps, Battery
Run
-Down Protection
9 HVAC Control Head (Manual)
10 Turn Signal
11 Cluster, Engine Control Module
12 Interior LightsFuse/Circuit
BreakerUsage
13 Auxiliary Power
14 Power Locks Motor
15 4WD Switch, Engine Controls
(VCM, PCM, Transmission)
16 Supplemental Inflatable Restraint
17 Front Wiper
18 Steering Wheel Radio Controls
19 Radio, Battery
20 Amplifier
21 HVAC (Manual),
HVAC I (Automatic),
HVAC Sensors (Automatic)
22 Anti
-Lock Brakes
23 Rear Wiper
24 Radio, Ignition
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