2003 GMC SONOMA bulb

Center High-Mounted Stoplamp
(CHMSL)
1. Remove the lens retaining screws.
2. Remove the lens.3. Remove the bulb.
4. Install a new bulb.
5. Reinstall the lens and tighten the screws.
If equipment such as a cap or camper is installed on
your vehicle, a center high-mounted stoplamp feed wire
is provided along the driver’s side rear frame. This
wire should be used to install a center high-mounted
stoplamp in the cap or camper.
5-54
2003 - Sonoma OM

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.
5-55
2003 - Sonoma OM

Audio System(s) (cont.)
Setting the Time for Radios with Radio
Data Systems (RDS)................................3-37
Setting the Time for Radios without Radio
Data Systems (RDS)................................3-36
Theft-Deterrent Feature................................3-67
Understanding Radio Reception.....................3-67
Automatic Headlamp System............................3-11
Automatic Transmission...................................2-22
Fluid..........................................................5-20
Operation...................................................2-25
Automatic Transmission Check..........................6-27
Automatic Transmission Shift Lock Control
System Check.............................................6-29
B
Backing Up....................................................4-58
Battery..........................................................5-42
Battery Replacement......................................... 2-6
Battery Rundown Protection.............................3-15
Bed Rails......................................................2-52
Before Leaving on a Long Trip.........................4-33
Before You Go Off-Roading..............................4-13
Body Lubrication Service..................................6-28
Brake
Parking......................................................2-32
System Inspection.......................................6-32Brake (cont.)
System Warning Light..................................3-27
Brake Adjustment............................................5-41
Brake Fluid....................................................5-39
Brake Pedal Travel.........................................5-41
Brake Wear...................................................5-41
Brakes..........................................................5-39
Braking........................................................... 4-5
Braking in Emergencies..................................... 4-7
Break-In, New Vehicle.....................................2-20
Bulb Replacement...........................................5-50
Center High-Mounted Stoplamp (CHMSL)........5-54
Halogen Bulbs............................................5-50
Headlamps.................................................5-50
One-Piece Front Turn Signal Lamps...............5-52
Replacement Bulbs......................................5-55
Taillamps....................................................5-55
Two-Piece Front Turn Signal Lamps...............5-53
Buying New Tires...........................................5-62
C
California Fuel.................................................. 5-5
Canada........................................................... 7-4
Canadian Owners................................................ ii
Canadian Roadside Assistance........................... 7-6
Capacities and Specifications............................5-94
Carbon Monoxide...................4-36, 4-51, 2-12, 2-37
2
2003 - Sonoma OM

Flat Tire........................................................5-67
Flat Tire, Changing.........................................5-68
Fluid
Automatic Transmission................................5-20
Manual Transmission....................................5-23
Power Steering...........................................5-37
Windshield Washer......................................5-38
FM ...............................................................3-67
Fog Lamps ....................................................3-13
Following Distance..........................................4-57
Four-Wheel Drive....................................2-29, 5-48
Front Axle......................................................5-49
Front Map Lamps...........................................3-14
Front Storage Area.........................................2-49
Fuel............................................................... 5-4
Additives...................................................... 5-5
California Fuel.............................................. 5-5
Filling a Portable Fuel Container..................... 5-8
Filling Your Tank........................................... 5-6
Fuels in Foreign Countries.............................. 5-6
Gage .........................................................3-35
Gasoline Octane........................................... 5-4
Gasoline Specifications.................................. 5-5
Low Warning Light.......................................3-35
System Inspection
.......................................6-31
Fuses
Fuses and Circuit Breakers
...........................5-89
Windshield Wiper
.........................................5-88G
Gage
Check Gages Warning Light..........................3-34
Engine Coolant Temperature.........................3-29
Fuel..........................................................3-35
Oil Pressure...............................................3-32
Speedometer..............................................3-23
Tachometer.................................................3-23
Voltmeter Gage...........................................3-26
Garment Hooks..............................................2-50
Gasoline
Octane........................................................ 5-4
Specifications............................................... 5-5
Getting Familiar with Off-Road Driving................4-16
Glass Surfaces...............................................5-81
Glove Box.....................................................2-41
GM Mobility Program for Persons with
Disabilities.................................................... 7-5
H
Hazard Warning Flashers................................... 3-3
Head Restraints............................................... 1-7
Headlamp High/Low-Beam Changer.................... 3-6
Headlamps....................................................5-50
Bulb Replacement.......................................5-50
Electrical System.........................................5-88
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2003 - Sonoma OM

Headlamps (cont.)
Halogen Bulbs............................................5-50
One-Piece Front Turn Signal Lamps...............5-52
Two-Piece Front Turn Signal Lamps...............5-53
Heated Seats................................................... 1-5
Heating.........................................................3-18
Highway Hypnosis...........................................4-34
Hill and Mountain Roads..................................4-34
Hitches..........................................................4-56
Hood
Checking Things Under.................................. 5-8
Release....................................................... 5-9
Horn ............................................................... 3-4
How to Add Coolant to the Coolant
Recovery Tank............................................5-32
How to Add Coolant to the Radiator..................5-34
How to Add Fluid....................................5-22, 5-24
How to Check................................5-20, 5-23, 5-59
How to Check and Add Fluid
............................5-25
How to Check Lubricant
..........................5-47, 5-49
How to Check Power Steering Fluid
..................5-37
How to Inspect the Engine Air Cleaner/Filter
.......5-19
How to Use This Manual
...................................... ii
How to Wear Safety Belts Properly
...................1-15
Hydraulic Clutch
.............................................5-24
Hydraulic Clutch System Check
........................6-27
Hydroplaning
..................................................4-30I
If No Steam Is Coming From Your Engine..........5-29
If Steam Is Coming From Your Engine...............5-28
If the Light Is Flashing.....................................3-30
If the Light Is On Steady.................................3-31
If You Are Stuck in Sand, Mud, Ice or Snow.......4-40
If You Do Decide To Pull A Trailer.....................4-52
If You’re Caught in a Blizzard...........................4-38
Ignition Positions.............................................2-20
Ignition Transmission Lock Check......................6-29
Infants and Young Children, Restraints...............1-32
Inflation–Tire Pressure...................................5-58
Inspection
Brake System.............................................6-32
Engine Cooling System................................6-31
Exhaust System..........................................6-31
Fuel System...............................................6-31
Part C - Periodic Maintenance.......................6-31
Steering, Suspension and Front Drive
Axle Boot and Seal..................................6-31
Throttle System...........................................6-32
Transfer Case and Front Axle
(Four-Wheel Drive)...................................6-32
Installing a Garage Door Opener.......................2-43
Instrument Panel
Cluster.......................................................3-21
Overview..................................................... 3-2
7
2003 - Sonoma OM

Rear Axle......................................................5-47
Locking........................................................ 4-7
Rear Door Security Locks................................2-11
Rear Seat Operation......................................... 1-9
Rear Seat Outside Passenger Positions.............1-26
Rear Seat Passengers, Safety Belts..........1-25, 1-26
Rearview Mirror, Automatic Dimming..................2-39
Rearview Mirrors.............................................2-39
Reclining Seatbacks.......................................... 1-6
Recreational Vehicle Towing.............................4-42
Regular Cab and Extended Cab Models.............1-60
Remote Keyless Entry System............................ 2-4
Remote Keyless Entry System, Operation............ 2-5
Removing the Flat Tire and Installing the
Spare Tire..................................................5-71
Removing the Spare Tire and Tools...................5-68
Removing Wheel Covers..................................5-70
Replacement Bulbs.........................................5-55
Replacing Brake System Parts..........................5-42
Replacing Restraint System Parts
After a Crash..............................................1-64
Reporting Safety Defects
Canadian Government................................... 7-9
General Motors............................................. 7-9
United States Government
.............................. 7-8
Restraint System Check
...................................6-26
Checking Your Restraint Systems
...................1-64
Replacing Restraint System Parts
After a Crash
..........................................1-64Restraint Systems
Checking....................................................1-64
Replacing Parts...........................................1-64
Retained Accessory Power (RAP)......................2-22
Right Front Passenger Position, Safety Belts......1-23
Roadside
Assistance Program....................................... 7-5
Rocking Your Vehicle To Get It Out...................4-40
Running Your Engine While You Are Parked.......2-38
S
Safety Belt
Reminder Light............................................3-23
Safety Belts
Care of ......................................................5-82
Center Passenger Position............................1-23
Driver Position............................................1-16
How to Wear Safety Belts Properly................1-15
Questions and Answers About
Safety Belts.............................................1-15
Rear Seat Passengers.........................1-25, 1-26
Right Front Passenger Position......................1-23
Safety Belt Extender....................................1-29
Safety Belt Use During Pregnancy.................1-22
Safety Belts Are for Everyone.......................1-10
Safety Chains.................................................4-56
Safety Warnings and Symbols.............................. iii
Scanning the Terrain.......................................4-16
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2003 - Sonoma OM