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Fuses Usage
RR Wiper Rear Window Wiper Switch
SEO ACCYSpecial Equipment Option
Accessory
WS WPR Windshield Wipers
TBC ACCYTruck Body Controller
Accessory
IGN 3 Rear Heated Seats Module
Fuses Usage
4WDFour-Wheel Drive Switch, Air
Suspension Switch/Module
HTR A/C Not Used
LOCKPower Door Lock Relay
(Lock Function)
HVAC 1Inside Rearview Mirror,
Climate Control System
L DOORDriver’s Door Harness
Connection
CRUISE Cruise Control
UNLOCKPower Door Lock Relay
(Unlock Function)
RR FOG LP Not Used
BRAKE Brake Switch
DRIVER UNLOCKPower Door Lock Relay
(Driver’s Door Unlock
Function)
IGN 0Brake Transmission Shift
Interlock, Powertrain Control
Module, Transmission
TBC IGN 0 Truck Body Controller
VEH CHMSLVehicle and Trailer High
Mounted Stoplamp
LT TRLR ST/TRN Left Turn Signal/Stop Trailer
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Fuses Usage
LT TRNLeft Turn Signals and
Sidemarkers
VEH STOPVehicle Stoplamps, Brake
Module, Electronic Throttle
Control Module
RT TRLR ST/TRN Right Turn Signal/Stop Trailer
RT TRNRight Turn Signals and
Sidemarkers
BODY Harness Connector
DDM Driver Door Module
LOCKSRear Doors and Liftgate
Power Lock Relay Feed
ECC Liftgate
TBC 2C Truck Body Controller
FLASH Flasher Module
CB LT DOORSLeft Rear Power Window
Circuit Breaker and Driver
Door Module
TBC 2B Truck Body Controller
TBC 2A Truck Body Controller
Circuit Breaker Usage
AUX PWR 2 Midgate Controller (SUT Only)
Center Instrument Panel Fuse Block
The center instrument panel utility block is
located underneath the instrument panel, to the
left of the steering column.
Device Usage
SEO Special Equipment Option
TRAILERTrailer Brake Wiring,
Off-Road Lamps Harness
Connector
UPFIT Up tter (Not Used)
SL RIDE Ride Control (Not Used)
HDLR 2Headliner Wiring
Connector 2
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Device Usage
BODY Body Wiring Connector
DEFOG Rear Defogger Relay
HDLNR 1 Headliner Wiring Connector 1
SPARE RELAY Not Used
CB SEATDriver and Passenger Seat
Module Circuit Breaker
CB RT DOORRear Right Power Window,
Passenger Door Module
SPARE Not Used
INFO Not UsedUnderhood Fuse Block
The underhood fuse block in the engine
compartment is located on the driver’s side of
the vehicle near the battery. Lift the cover for
access to the fuse/relay block.
To remove fuses if you don’t have a fuse extractor,
hold the end of the fuse between your thumb
and index nger and pull straight out.
SeeEngine Compartment Overview on page 402
for more information on its location.
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Page 509 of 570

*1— Gasoline Engine and Fuel Injection Rail #2.
*2— Gasoline Engine and Fuel Injection Rail
#1.
*3— Gasoline Engine; Oxygen Sensors.
*4— Gasoline Engine; Oxygen Sensors.
*5— Ignition 1
*6— Powertrain Control Module, Fuel Pump.
*7— Supplemental Brake Assist.
*8— Sunroof.
Fuses Usage
GLOW PLUG Not Used
CUST FEED Gasoline Accessory Power
HYBRID Not Used
WSW/HTRHeated Windshield Washer
(Special Edition Only)
STUD #1Accessory Power/Trailer
Wiring
MBEC 1Mid Bussed Electrical Center
Power Feed, Front Seats,
Right Doors
Fuses Usage
BLWR Front Climate Control Fan
LBEC 2Left Bussed Electrical Center,
Door Modules, Door Locks,
Auxiliary Power Outlet—Rear
Cargo Area and Instrument
Panel
STUD #2*Accessory Power/Trailer
Wiring Brake Feed
ABS Anti-lock Brakes
VSES/ECASElectronically Controlled Air
Suspension
IGN A Ignition Switch
IGN B Ignition Switch
LBEC 1Left Bussed Electrical Center,
Left Doors, Truck Body
Controller, Flasher Module
TRL PARK Parking Lamps Trailer Wiring
RR PARKPassenger’s Side Rear
Parking and Sidemarker
Lamps
LR PARKDriver’s Side Rear Parking
and Sidemarker Lamps
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Fuses Usage
PARK LP Parking Lamps Relay
STRTR Starter Relay
INTPARK Roof Marker Lamps
STOP LP Stoplamps
TBC BATTTruck Body Controller
Battery Feed
SEO B2 Off-Road Lamps
4WS Not Used
AUX PWRInstrument Panel Outlets,
Rear Cargo Area Power
Outlets, Console
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, Electronic Brake
Controller TC2 Mode Switch
RTDElectronic Brake Controller
Battery FeedFuses Usage
TRL B/U Backup Lamps Trailer Wiring
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
AIRBAGSupplemental In atable
Restraint System
FRT PARKFront Parking Lamps,
Sidemarker Lamps
DRLDaytime Running Lamps
(Relay)
SEO IGN Rear Defog Relay
TBC IGN1 Truck Body Controller Ignition
HI HDLP-LTDriver’s Side High Beam
Headlamp
LH HID Not Used
DRL Daytime Running Lamps
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Fuses Usage
RVC Regulated Voltage Control
IPC/DICInstrument Panel Cluster/
Driver Information Center
HVAC/ECASClimate Control
Controller/Electronically
Controlled Air Suspension
CIG LTR Cigarette Lighter
HI HDLP-RTPassenger’s Side High Beam
Headlamp
HDLP-LOW Headlamp Low Beam Relay
A/C COMPAir Conditioning
Compressor Relay
A/C COMP Air Conditioning Compressor
TCMB Transmission Control Module
RR WPR Rear Wiper/Washer
RADIO Audio System
SEO B1Mid Bussed Electrical Center,
Universal Home Remote
System, Rear Heated Seats
LO HDLP-LTDriver’s Side Headlamp
Low BeamFuses Usage
BTSIBrake Transmission Shift
Interlock System
CRNK Starting System
LO HDLP-RTPassenger’s Side Headlamp
Low Beam
FOG LP Not Used
FOG LP Not Used
HORN Horn Relay
W/S WASHWindshield and Rear Window
Washer Pump Relay
W/S WASHWindshield and Rear Window
Washer Pump
INFO OnStar
®
RADIO AMP Radio Ampli er
RH HID Not Used
HORN Horn
EAP Not Used
TREC Four-Wheel Drive Module
SBA Not Used
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