2003 GMC SONOMA high center stop lamp

Service............................................................5-3
Doing Your Own Service Work.........................5-3
Adding Equipment to the Outside of
Your Vehicle..............................................5-4
Fuel................................................................5-4
Gasoline Octane............................................5-4
Gasoline Specifications....................................5-5
California Fuel...............................................5-5
Additives.......................................................5-5
Fuels in Foreign Countries...............................5-6
Filling Your Tank............................................5-6
Filling a Portable Fuel Container.......................5-8
Checking Things Under
the Hood......................................................5-8
Hood Release................................................5-9
Engine Compartment Overview.......................5-10
Engine Oil...................................................5-13
Engine Air Cleaner/Filter................................5-18
Automatic Transmission Fluid
.........................5-20
Manual Transmission Fluid
.............................5-23
Hydraulic Clutch
...........................................5-24Engine Coolant.............................................5-25
Radiator Pressure Cap..................................5-27
Engine Overheating.......................................5-28
Cooling System............................................5-30
Engine Fan Noise.........................................5-36
Power Steering Fluid.....................................5-37
Windshield Washer Fluid................................5-38
Brakes........................................................5-39
Battery........................................................5-42
Jump Starting...............................................5-43
Rear Axle.......................................................5-47
Four-Wheel Drive............................................5-48
Front Axle......................................................5-49
Bulb Replacement..........................................5-50
Halogen Bulbs..............................................5-50
Headlamps..................................................5-50
One-Piece Front Turn Signal Lamps................5-52
Two-Piece Front Turn Signal Lamps................5-53
Center High-Mounted Stoplamp (CHMSL).........5-54
Taillamps.....................................................5-55
Replacement Bulbs.......................................5-55
Section 5 Service and Appearance Care
5-1
2003 - Sonoma OM

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

Fuse Usage
W/W PMP Not Used
HORN Horn
BTSI Automatic Transmission Shift Lock
Control System
B/U LP Back Up Lamps
IGN B Column Feed,Ignition 2, 3, 4
STARTER Starter
RAP Retained Accessory Power
LD LEV Not Used
OXYSEN Oxygen Sensor
IGN E Engine
MIR/LKS Mirrors, Door Locks
FOG LP Fog Lamps
IGN A Starting and Charging Ignition 1
STUD #2 Accessory Feeds, Electric Brake
PARKLP Parking Lamps
LR PRK Left Rear Parking Lamps
LIFTGLASS Liftglass
IGN C Starter Solenoid, Fuel Pump,
PRNDL
HTDSEAT Heated SeatFuse Usage
HVAC Heating,Ventilation, Air Cooling
System
TRCHMSL Trailer Center High Mount Stop Light
RRDFOG Rear Defogger
TBC Truck Body Computer
CRANK Clutch Switch, NSBU Switch
CHMSL Center High Mounted Stoplamp
HAZLP Hazard Lamps
VECHMSL Vehicle Center High-Mounted
Stop Lamp
RR DEFOG Rear Defogger
HTDMIR Heated Mirror
ATC Transfer Case (Four-Wheel Drive)
STOPLP Stop Lamps
RR W/W Rear Window Wiper
5-93
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

Care of
Safety Belts................................................5-82
Your Cassette Tape Player............................3-68
Your CD Player...........................................3-69
Your CDs ...................................................3-69
Cassette Tape Messages.................................3-54
Cassette Tape Player Service...........................6-26
Center High-Mounted Stoplamp (CHMSL)...........5-54
Center Passenger Position, Safety Belts.............1-23
Chains, Tires..................................................5-66
Charging System Light....................................3-26
Check
Engine Light...............................................3-29
Gages Warning Light
...................................3-34
Checking Brake Fluid
......................................5-40
Checking Coolant
............................................5-26
Checking Engine Oil
........................................5-13
Checking the Fluid Level
..................................5-21
Checking Things Under the Hood
....................... 5-8
Checking Your Restraint Systems
......................1-64
Chemical Paint Spotting
...................................5-85
Child Restraints
Child Restraint Systems
...............................1-36
Infants and Young Children
...........................1-32
Lower Anchorages and Top Tethers for
Children (LATCH System)
..........................1-44
Older Children
.............................................1-30Child Restraints (cont.)
Securing a Child Restraint Designed for
the LATCH System...................................1-46
Securing a Child Restraint in a Center
Seat Position...........................................1-49
Securing a Child Restraint in a Rear
Outside Seat Position...............................1-46
Securing a Child Restraint in the Right
Front Seat Position...................................1-49
Top Strap...................................................1-41
Top Strap Anchor Location............................1-43
Where to Put the Restraint...................1-39, 1-40
Cigarette Lighter.............................................3-16
Cleaning
Inside of Your Vehicle..................................5-79
Outside of Your Vehicle................................5-82
Underbody Maintenance...............................5-85
Weatherstrips..............................................5-82
Cleaning Exterior Lamps/Lenses.......................5-83
Cleaning the Mirror.........................................2-39
Cleaning the Photocells...................................2-39
Climate Control System...................................3-17
Outlet Adjustment........................................3-19
Clutch, Hydraulic.............................................5-24
Compact Disc Messages.................3-46, 3-56, 3-67
Compact Spare Tire........................................5-78
Content Theft-Deferrent....................................2-17
Control of a Vehicle.......................................... 4-5
3
2003 - Sonoma OM