2003 GMC SONOMA headlamp

Bulb Replacement
SeeReplacement Bulbs on page 5-55for the proper
types of bulbs to use. For any bulb changing procedure
not listed in this section, contact your GM dealer’s
service department.
Halogen Bulbs
{CAUTION:
Halogen bulbs have pressurized gas inside
and can burst if you drop or scratch the bulb.
You or others could be injured. Be sure to
read and follow the instructions on the bulb
package.
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.
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5. Turn the bulb assembly counterclockwise to
remove it from the headlamp assembly.
6. Put the new bulb into the bulb assembly and
reinstall it in the headlamp assembly by turning
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.
10. Close the hood.
Two-Piece Composite Headlamp
System
1. Open the hood.
2. Remove the black retainer clips by lifting up.
3. Unplug the electrical connector.
4. Pull the headlamp lens assembly out.
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5. Turn the bulb assembly counterclockwise to remove
it from the headlamp assembly.
6. Put the new bulb into the bulb assembly and
reinstall it in the headlamp assembly by turning
it clockwise until it is tight.
7. Plug in the electrical connector.
8. Put the headlamp lens assembly back into the
vehicle.
9. Install the two retaining clips.
10. Close the hood.
One-Piece Front Turn Signal Lamps
1. Remove the headlamp assembly as shown in
″One-Piece Composite Headlamp System″
underHeadlamps on page 5-50.
2. Twist the bulb socket
counterclockwise
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
twist it clockwise until it is tight.
6. Put the headlamp assembly back into the vehicle.
7. Install the two retaining clips.
8. Close the hood.
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Two-Piece Front Turn Signal Lamps
1. Remove the headlamp assembly as shown in
″Two-Piece Composite Headlamp System″
underHeadlamps on page 5-50.
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. Pull the bulb straight out to remove it
from the socket.
5. Push the new bulb into the socket until it snaps
into place.
6. Put the socket into the lamp assembly and turn it
clockwise until it is tight.
7. 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.
8. Install the two retaining clips.
9. Close the hood.
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Taillamps
1. Open the tailgate.
2. Remove the screws
from the lamp
assembly near the
tailgate latch.
3. Pull the assembly away from the pickup side panel.
4. Turn the socket counterclockwise to remove it.
Push the tab in while you turn the socket.
5. Pull the bulb out.
6. Push the new bulb into the socket.
7. Put the socket into the assembly and turn the
socket clockwise until it locks in place.
8. Reinstall the assembly. Install and tighten the
screws.
9. Close the tailgate.
Replacement Bulbs
Exterior Lamp Bulb Number
Halogen Headlamps
Composite Low-Beam
Composite High-Beam9006 HB4 or
9006 LL
9005 HB3
Tail and Stoplamps 3057
Rear Sidemarker Lamps 194
Front Sidemarker Lamps 194NA
Front Turn Signal Lamps 3457A
Center High–Mounted Stoplamp 211–2
*For replacement bulbs not listed here,
please consult your dealer.
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Wheel Replacement
Replace any wheel that is bent, cracked or badly rusted
or corroded. If wheel nuts keep coming loose, the
wheel, wheel bolts and wheel nuts should be replaced.
If the wheel leaks air, replace it (except some
aluminum wheels, which can sometimes be repaired).
See your dealer if any of these conditions exist.
Your dealer will know the kind of wheel you need.
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.
SeeChanging a Flat Tire on page 5-68for more
information.
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Service Parts Identication Label
You’llfind this label on the inside of the glove box.
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 dealerrst. 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
Servicing Your Air Bag-Equipped Vehicle on page 1-63.
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 Wiper Fuses
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 itfixed.
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 isfixed or goes away.
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Fuse Usage
A Not Used
B Not Used
1 Not Used
2 Cigarette Lighter, Data Link
Connector
3 Cruise Control Module and Switch,
Body Control Module, Heated SeatsFuse Usage
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 Heating, Ventilation, Air Cooling
Control Head (Manual)
10 Turn Signal
11 Cluster, Engine Control Module
12 Interior Lights
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
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