2001 GMC YUKON XL DENALI turn signal

6-36
A. Low-Beam Headlamp B. High-Beam Headlamp
1. Pull the headlamp assembly out.
2. Unplug the electrical connector.
3. Turn the bulb counterclockwise and remove it from
the headlamp assembly.
4. Put the new bulb into the headlamp assembly and
turn it clockwise until it is tight. Use care not to
touch the bulb with your fingers or hands.
5. Plug in the electrical connector.
6. Put the headlamp assembly back into the vehicle.
7. Install and tighten the two pins.
Front Turn Signal, Sidemarker and
Daytime Running Lamps
A. Sidemarker Lamp
B. Retainer Clip
C. Front Turn Signal Lamp
D. Daytime Running Lamp

6-37
1. Remove the headlamp assembly as
mentioned previously.
2. Press the retainer clip (B), located behind the turn
signal housing, towards the outside of the vehicle.3. Pull the turn signal housing out from the vehicle.
4. Press the locking release lever, turn the bulb
socket counterclockwise and remove it from the
turn signal housing.
5. Remove the bulb from the bulb socket.
6. Put the new bulb into the bulb socket.
7. Put the bulb socket into the turn signal housing and
turn it clockwise until it locks.
8. Put the turn signal housing back onto the vehicle
placing the hook and posts on the inner side into the
alignment holes first and then the outer side into the
retainer bracket until you hear a click.
9. Put the headlamp lens assembly back into
the vehicle.

6-38 Taillamps
A. Turn Signal Lamp
B. Back
-Up Lamp
C. Stoplamp
1. Use a screwdriver to
remove the two screws
from the rear
lamp assembly.2. Remove the rear lamp assembly.
3. Press the release tab and turn the bulb
socket counterclockwise to remove it from the
taillamp housing.
4. Pull the bulb straight out
from the socket.
5. Press a new bulb into the socket, insert it into the
taillamp housing and turn the socket clockwise into
the taillamp housing until it clicks.
6. Reinstall the rear lamp assembly and tighten
the screws.

6-60
NAME Usage
HVAC 1 Climate Control System
CRUISE Cruise Control, Instrument Cluster
IGN 3 Ignition, Power Seats
4WD Not Used
CRANK Starting System
INT PRK Parking Lamps, Sidemarker
Lamps, Interior Lamps
L DOOR Power Door Lock Relay
BRAKE Anti
-Lock Brake System
RR WIPER Rear Window Wiper
ILLUM Interior Lamps
SEAT Power Seat Circuit Breaker
TURN Exterior Lamps, Turn Signals,
Hazard Lamps
UNLOCK Power Door Locks
HTR A/C Climate Control SystemNAME Usage
WS WPR Windshield Wipers
IGN 1 Ignition, Instrument Panel
AIR BAG Air Bag
MIR/LOCK Power Mirrors, Power Door Locks
DR LOCK Power Door Locks
PWR WDO Power Window Circuit Breaker
UNLOCK Power Door Lock Relay
IGN 0 PRND321 Display,
Odometer, VCM/PCM
SEO IGN Special Equipment
Option, Ignition
SEO ACCY Special Equipment Option
Accessory, Cellular Telephone
RAP #1 Retained Accessory Power Relay
RDO 1 Audio System
RAP #2 Rear Power Windows,
Sunroof, Radio

6-64
Name Usage
STUD #1 Accessory Power/Trailer Wiring
Feed/Load Leveling
ABS Anti
-Lock Brakes
IGN A Ignition Switch
AIR A.I.R. System
RAP #1 Retained Accessory Power, Power
Mirrors, Power Door Locks,
Power Seat(s)
IGN B Ignition Switch
RAP #2 Retained Accessory Power/Rear
Power Windows, Sunroof, Radio
STUD #2 Accessory Power/Trailer Wiring
Brake Feed
TRL R TRN Right Turn Signal Trailer Wiring
TRL L TRN Left Turn Signal Trailer Wiring
IGN 1 Ignition, Fuel Controls
INJ
-B Ignition, Fuel Controls (Relay)
STARTER Starter (Relay)
PARK LP Parking Lamps
FRT HVAC Climate Control System
STOP LP Exterior Lamps, Stoplamps
ECM 1 VCM/PCMName Usage
CHMSL Center High Mounted Stoplamp
VEH STOP Stoplamps, Cruise Control
TRL B/U Backup Lamps Trailer Wiring
INJ
-A Fuel Controls, Ignition
RR HVAC Rear HVAC
VEH B/U Vehicle Backup Lamps
ENG 1 Engine Controls, Canister Purge,
Fuel System
ETC Electronic Throttle Control
IGN E A/C Compressor Relay, Rear
Window Defogger, Daytime
Running Lamps, A.I.R. System
B/U LP Backup Lamps, Automatic
Transmission Shift Lock
Control System
ATC Automatic Transfer Case
RR DEFOG Rear Window Defogger,
Heated Mirrors (Relay)
RTD Autoride
(Real Time Damping)
RR PRK Right Rear Parking Lamps
ECM B VCM/PCM
F/PMP Fuel Pump (Relay)

6-65
Name Usage
O2 A Oxygen Sensors
O2 B Oxygen Sensors
LR PRK Left Rear Parking Lamps
RR DEFOG Rear Window Defogger,
Heated Mirrors
HDLP Headlamps (Relay)
TRL PRK Parking Lamps Trailer Wiring
PRIME Not Used
RT HDLP Right Headlamps
DRL Daytime Running Lamps (Relay)
HTD MIR Heated Mirrors
LT HDLP Left Headlamps
A/C Air Conditioning
AUX PWR Cigarette Lighter, Auxiliary
Power Outlets
SEO 2 Special Equipment Option Power,
Power Seats, Aux Roof Mnt Lamp
SEO 1 Special Equipment Option Power,
Aux Roof Mnt Lamp, Cell Phone
DRL Daytime Running Lamps
A/C A/C (Relay)
FOG LP Fog LampsName Usage
FOG LP Fog Lamps (Relay)
RADIO Audio System, Instrument Cluster,
Climate Control System
CIGAR Cigarette Lighter, Auxiliary
Power Outlets
RT TURN Right Turn Signals
BTSI Automatic Transmission Shift
Lock Control System
LT TURN Left Turn Signals
FR PRK Front Parking Lamps,
Sidemarker Lamps
W/W PMP Windshield Washer Pump
HORN Horn (Relay)
IGN C Ignition Switch, Fuel Pump,
PRND321 Display, Crank
RDO AMP Radio Amplifier
HAZ LP Exterior Lamps, Hazard Lamps
EXP LPS Not Used
HORN Horn
CTSY LP Interior Lamps
RR WPR Rear Wipers
TBC Body Control Module, Remote
Keyless Entry, Headlamps