2003 GMC SIERRA low beam

3. Press the release tab and turn the bulb socket
counterclockwise to remove it from the taillamp
housing.
4. Pull the old bulb straight out from the socket.
5. Press a new bulb into the socket and turn the socket
clockwise into the taillamp housing until it clicks.
6. Reinstall the rear lamp assembly.
7. Close the tailgate.
Replacement Bulbs
Exterior Lamp Bulb Number
Low-Beam Headlamps 9005 or
9005 LL
(long life)
High-Beam Headlamps 9005
Daytime Running Lamps (DRL) 4114K
Front Roof Marker Lamps 194
Front Parking and Turn Lamps 3457A
Rear Marker Lamps, Taillamp and
Stoplamps3157
Rear Turn Lamps 3157
Back-up Lamps 3157
Center High-Mounted Stoplamp 912
Cargo Lamp 912
Fender Marker Lamps 194
For any bulb not listed here contact your dealer.
5-55
2003 - Sierra Denali

Fuses Usage
IGN 1 Ignition Relay
PCM 1 Powertrain Control Module
ETC/ECMElectronic Throttle Control,
Electronic Brake Controller
IGN EInstrument Panel Cluster, Air
Conditioning Relay, Turn
Signal/Hazard Switch, Starter
Relay
RTD Ride Control
TRL B/U Backup Lamps Trailer Wiring
PCM BPowertrain Control Module,
Fuel Pump
F/PMP Fuel Pump (Relay)
B/U LPBack-up Lamps, Automatic
Transmission Shift Lock
Control System
RR DEFOG Rear Window Defogger
HDLP-HI Headlamp High Beam Relay
PRIME Not Used
02B Oxygen Sensors
SIRSupplemental Inflatable
Restraint System
FRT PARKFront Parking Lamps,
Sidemarker Lamps
DRLDaytime Running Lamps
(Relay)Fuses Usage
SEO IGN Rear Defog Relay
TBC IGN1 Truck Body Controller Ignition
HI HDLP-LT High Beam Headlamp-Left
LH HID Not Used
DRL Daytime Running Lamps
IPC/DICInstrument Panel
Cluster/Driver Information
Center
HVAC/ECAS Climate Control Controller
CIG LTR Cigarette Lighter
HI HDLP-RT High Beam Headlamp-Right
HDLP-LOW Headlamp Low Beam Relay
A/C COMP Air Conditioning Compressor
A/C COMPAir Conditioning Compressor
Relay
RR WPR Not Used
RADIO Audio System
SEO B1Mid Bussed Electrical Center,
Rear Heated Seats,
HomeLink
LO HDLP-LT Headlamp Low Beam-Left
BTSIBrake Transmission Shift
Interlock System
CRANK Starting System
LO HDLP-RT Headlamp Low Beam-Right
5-98
2003 - Sierra Denali

H
Hazard Warning Flashers................................... 3-4
Head Restraints............................................... 1-5
Headlamp High/Low Beam Changer.................... 3-6
Headlamps....................................................5-48
Bulb Replacement.......................................5-48
Front Turn Signal, Sidemarker and Daytime
Running Lamps........................................5-49
Halogen Bulbs............................................5-48
Pickup Box Identification and Fender
Marker Lamps.........................................5-54
Roof Marker Lamps.....................................5-51
Heated Seats................................................... 1-3
Heating.........................................................3-22
Highway Hypnosis...........................................4-38
Hill and Mountain Roads..................................4-38
Hitches..........................................................4-57
HomeLink
®Transmitter, Programming................2-35
HomeLink®Transmitter....................................2-35
Hood
Checking Things Under................................5-10
Release.....................................................5-10
Horn ............................................................... 3-5
How to Add Coolant to the Coolant Surge Tank......5-30
How to Add Fluid............................................5-22
How to Check........................................5-20, 5-57
How to Check Lubricant...................................5-46
How to Check Power Steering Fluid..................5-35How to Inspect...............................................5-18
How to Use This Manual...................................... ii
How to Wear Safety Belts Properly...................1-12
Hydroplaning..................................................4-33
I
If No Steam Is Coming From Your Engine..........5-28
If Steam Is Coming From Your Engine...............5-27
If the Light is Flashing.....................................3-38
If the Light Is On Steady.................................3-38
If You Are Stuck in Sand, Mud, Ice or Snow.......4-44
If You Do Decide To Pull A Trailer.....................4-53
If You’re Caught in a Blizzard...........................4-42
Ignition Positions.............................................2-16
Ignition Transmission Lock Check......................6-13
Illuminated Visor Vanity Mirrors.........................2-13
Infants and Young Children, Restraints...............1-31
Inflation -- Tire Pressure..................................5-57
Inspection
Brake System
.............................................6-15
Engine Cooling System
................................6-14
Exhaust System
..........................................6-14
Fuel System
...............................................6-14
Part C - Periodic Maintenance
.......................6-14
Steering and Suspension
..............................6-14
Transfer Case and Front Axle
(All-Wheel Drive)
......................................6-15
7
2003 - Sierra Denali