Page 370 of 419
6-67
Underhood Electrical Center
The underhood electrical center is located on the
driver's side of the engine compartment near the battery.
Lift the cover for access to the fuse/relay block.You will see fuses to the top right of the fuse/relay
center block once you remove the cover. These are
spare fuses and can be used accordingly.
You can remove fuses with a fuse extractor. The fuse
extractor is located in the underhood electrical center.
To remove fuses if you don't have a fuse extractor, hold
the end of the fuse between your thumb and index finger
and pull straight out.
See ªEngine Compartment Overviewº in the Index for
more information.
Page 372 of 419

6-69
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 LampsName Usage
FRT HVAC Climate Control System
STOP LP Exterior Lamps, Stoplamps
ECM I PCM
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
Page 373 of 419

6-70
Name Usage
RR DEFOG Rear Window Defogger,
Heated Mirrors (Relay)
RTD Autoride (Real Time Damping)
RR PRK Right Rear Parking Lamps
ECM B PCM
F/PMP Fuel Pump (Relay)
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 HeadlampsName Usage
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, Onstar
DRL Daytime Running Lamps
A/C A/C (Relay)
FOG LP Fog Lamps
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
Page 397 of 419

7-19 At Least Once a Year
Key Lock Cylinders Service
Lubricate the key lock cylinders with the lubricant
specified in Part D.
Body Lubrication Service
Lubricate all hood latch assembly, secondary latch,
pivots, spring anchor, release pawl, rear compartment
hinges, outer liftgate handle pivot points, rear door
detent link, roller mechanism, liftgate handle pivot
points, latch bolt, fuel door hinge, cargo door hinge,
locks and folding seat hardware. Part D tells you what
to use. More frequent lubrication may be required when
exposed to a corrosive environment.Starter Switch Check
CAUTION:
When you are doing this check, the vehicle could
move suddenly. If it does, you or others could be
injured. Follow the steps below.
1. Before you start, be sure you have enough room
around the vehicle.
2. Firmly apply both the parking brake and the regular
brake. See ªParking Brakeº in the Index if necessary.
NOTE: Do not use the accelerator pedal, and be
ready to turn off the engine immediately if it starts.
3. Try to start the engine in each gear. The starter
should work only in PARK (P) or NEUTRAL (N).
If the starter works in any other position, your
vehicle needs service.
Page 398 of 419

7-20
Automatic Transmission Shift Lock Control
System Check
CAUTION:
When you are doing this check, the vehicle could
move suddenly. If it does, you or others could be
injured. Follow the steps below.
1. Before you start, be sure you have enough room
around the vehicle. It should be parked on a
level surface.
2. Firmly apply the parking brake. See ªParking Brakeº
in the Index if necessary.
NOTE: Be ready to apply the regular brake
immediately if the vehicle begins to move.3. With the engine off, turn the key to the RUN
position, but don't start the engine. Without applying
the regular brake, try to move the shift lever out
of PARK (P) with normal effort. If the shift lever
moves out of PARK (P), your vehicle needs service.
Ignition Transmission Lock Check
While parked, and with the parking brake set, try to turn
the ignition key to LOCK in each shift lever position.
The key should turn to LOCK only when the shift
lever is in PARK (P).
The key should come out only in LOCK.
Page 403 of 419

7-25
USAGEFLUID/LUBRICANT
Key
Lock CylindersMulti-Purpose Lubricant,
Superlube (GM Part
No. 12346241 or equivalent).
Floor
Shift LinkageLubriplate Lubricant Aerosol
(GM Part No. 12346293 or
equivalent) or lubricant meeting
requirements of NLGI # 2
Category LB or GC
-LB.
Chassis
LubricationChassis Lubricant (GM Part
No. 12377985 or equivalent)
or lubricant meeting requirements
of NLGI # 2, Category LB
or GC
-LB.
Front AxleSAE 80W-90 Axle Lubricant (GM
Part No. 1052271 or equivalent).
USAGEFLUID/LUBRICANT
Rear AxleSAE 75W-90 Synthetic Axle
Lubricant (GM Part No. 12378261)
or equivalent meeting GM
Specification 9986115.
Automatic
Transfer CaseAUTO-TRAK II Fluid
(GM Part No. 12378508).
Front Axle
Propshaft Spline
or One
-Piece
Propshaft Spline
(Two
-Wheel
Drive with
Auto. Trans.)
Spline Lubricant, Special Lubricant
(GM Part No. 12345879) or
lubricant meeting requirements
of GM 9985830.
Hood Latch
Assembly,
Secondary Latch,
Pivots, Spring
Anchor and
Release PawlLubriplate Lubricant Aerosol
(GM Part No. 12346293 or
equivalent) or lubricant meeting
requirements of NLGI # 2,
Category LB or GC
-LB.
Page 412 of 419

8-6
Roadside Assistance
GMC's Roadside Assistance provides stranded owners
with over
-the-phone roadside repairs, location of the
nearest GMC dealer or the following special services:
Flat Tire Change: Installation of spare tire will be
covered at no charge (customer is responsible for repair
or replacement of tire).Fuel Delivery: Delivery of enough fuel for the customer
to get to the nearest service station (up to $5.00) will
be covered.
Jump Start: No
-start situations which require a battery
jump start will be covered at no charge.
Lock Out: Replacement keys or locksmith service will
be covered at no charge if you are unable to gain entry
into your vehicle. Delivery of the replacement key will
be covered at no charge within 10 miles (16 km).
Emergency Towing Service: Towing to the nearest
GMC dealer for warranty related disablements will
be covered.
Trip Routing: Custom
-made, computerized highlighted
maps using the most direct or scenic route are provided
free of charge. Maps include points of interest and a list
of GMC dealers along the route. Also included is a list
of hotels along the route that are discounted through
affiliation with ªQuest International.º Trip Routing is
available through Roadside Assistance by calling
1
-800-GMC-8782 (462-8782). Please be prepared to
provide your Vehicle Identification Number (VIN).
Allow five working days for fulfillment.