In this article you will find a description of fuses and relays GMC,
with photos of block diagrams and their locations.
Highlighted the cigarette lighter fuse (as the most popular thing people look for).
Get tips on blown fuses, replacing a fuse, and more.
Instrument Panel Fuse Block
The fuse block access door is on the driver’s side edge of the instrument panel. Pull off the cover to access the fuse block.
Name | Usage |
L BODY | Retained Accessory Power Relay |
LOCK | Power Door Locks |
DRV UNLOCK | Power Door Lock Relay |
LOCK | Power Door Lock Relay |
HVAC 1 | Climate Control System |
CRUISE | Cruise Control, Instrument Panel Cluster |
IGN 3 | Ignition, Power Seats |
4WD | Four-Wheel Drive System, Auxiliary Battery |
CRANK | Starting System |
INT PRK | Parking Lamps, Sidemarker Lamps, Interior Lamps |
L DOOR | Power Door Lock Relay |
BRAKE | Anti-Lock Brake System |
RR WIPER | Not Used |
ILLUM | Interior Lamps |
SEAT | Power Seat Circuit Breaker |
TURN | Exterior Lamps, Turn Signals, Hazard Lamps |
UNLOCK | Power Door Locks |
HTR A/C | Climate Control System |
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, PCM |
SEO IGN | Special Equipment Option, Ignition, Manual Selectable Ride |
SEO ACCY | Special Equipment Option Accessory, Cellular Telephone |
RAP #1 | Retained Accessory Power Relay |
RDO 1 | Audio System |
RAP #2 | Not Used |
Center Instrument Panel Utility Block
The center instrument panel utility block is located underneath the instrument panel, to the left of the steering column.
Name | Usage |
SEO | Special Equipment Option |
HTD ST | Heated Seats |
SPARE 4 | Not Used |
VANITY | Headliner Wiring |
TRAILER | Trailer Brake Wiring |
PWR ST | Power Seats |
SPARE 5 | Not Used |
CLUTCH | Manual Transmission Clutch Switch |
UPF | Upfitter |
PARK LAMP | Parking Lamps (Relay) |
FRT PRK EXPT | Not Used (Fuse) |
SL RIDE | Manual Selectable Ride Switch |
SPARE 2 | Not Used |
RR PRK LP | Not Used (Relay) |
RR FOG LP | Not Used (Relay) |
SPARE 3 | Not Used |
INADV PWR | Interior Lights Feed |
CTSY LP | Courtesy Lamps |
CEL PHONE | Cellular Telephone Wiring |
Underhood Electrical Center
The underhood electrical center is located on the driver’s side of the engine compartment near the battery.
*1 INJ B–Gasoline Engine and Diesel Engine.
*2 ECM I–Gasoline Engine; ECMRPV–Diesel Engine.
*3 02 A–Gasoline Engine; FUEL HT–Diesel Engine.
*4 02 B–Gasoline Engine; ECM I–Diesel Engine.
Name | Usage |
GLOW PLUG | Diesel Glow Plugs and Intake Air Heater |
CUST FEED | Gasoline Accessory Power |
STUD #1 | Accessory Power/Trailer Wiring Feed |
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 | Not Used |
STUD #2 | Accessory Power/Trailer Wiring Brake Feed |
SPARE | Spare Fuse |
TRL R TRN | Right Turn Signal Trailer Wiring |
TRL L TRN | Left Turn Signal Trailer Wiring |
IGN 1 | Ignition, Fuel Controls (Relay) |
INJ B | Ignition, Fuel Controls |
STARTER | Starter (Relay) |
PARK LP | Parking Lamps |
FRT HVAC | Climate Control System |
STOP LP | Exterior Lamps, Stoplamps |
ECM I | PCM |
ECMRPV | Fuel Controls, ECM |
CHMSL | Center High Mounted Stoplamp |
VEH STOP | Stoplamps, Cruise Control |
TRL B/U | Backup Lamps Trailer Wiring |
INJ A | Fuel Controls, Ignition |
RR HVAC | Not Used |
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) |
RR PRK | Right Rear Parking Lamps |
ECM B | PCM |
F/PMP | Fuel Pump (Relay) |
O2 A | Oxygen Sensors |
FUEL HT | Fuel Heater, Glow Plug and Intake Heater Controls |
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 |
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, 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 |
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 | Not Used |
HAZ LP | Exterior Lamps, Hazard Lamps |
EXP LPS | Not Used |
HORN | Horn |
CTSY LP | Interior Lamps |
RR WPR | Not Used |
TBC | Body Control Module, Remote Keyless Entry, Headlamps |
WARNING: Terminal and harness assignments for individual connectors will vary depending on vehicle equipment level, model, and market.
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