Page 400 of 594

Auxiliary Battery
The auxiliary battery provision can be used to supply
electrical power to additional equipment that you
may choose to add, such as a slide-in camper.
If your vehicle has this
provision, this relay will be
located on the passenger’s
side of the vehicle, next
to the auxiliary battery.
When using this provision, connection should only be
made to the upper stud (A) of the relay. Do not
make connections to the lower stud (B) of the relay.The auxiliary battery circuit is protected by a megafuse
located behind the auxiliary battery.
Be sure to follow the proper installation instructions that
are included with any electrical equipment that you
install.
Notice:Leaving electrical equipment on for
extended periods will drain the battery. Always turn
off electrical equipment when not in use and do
not use equipment that exceeds the maximum
amperage rating for the auxiliary battery provision.
Power Winches
If you wish to use a power winch on your vehicle, only
use it when your vehicle is stationary or anchored.
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Fuses Usage
RR WPR Not Used
SEO ACCYSpecial Equipment Option
Accessory
WS WPR Windshield Wipers
TBC ACCYTruck Body Controller
Accessory
IGN 3 Ignition, Heated Seats
Fuses Usage
4WDFour-Wheel Drive System,
Auxiliary Battery
HTR A/C Climate Control System
LOCK (Relay)Power Door Lock Relay
(Lock Function)
HVAC 1 Climate Control System
LT DRDriver’s Door Harness
Connection
CRUISECruise Control, Power Take
Off (PTO)
UNLCK (Relay)Power Door Lock Relay
(Unlock Function)
RR FOG LP Not Used
BRAKE Anti-Lock Brake System
DRIVER UNLCKPower Door Lock Relay
(Driver’s Door Unlock
Function)
IGN 0 TCM
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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Page 533 of 594
Device Usage
HDLR 2 Headliner Wiring Connector
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 DOORRight Power Windows Circuit
Breaker
SPARE Not Used
INFOInfotainment Harness
ConnectionUnderhood Fuse Block
The underhood fuse block in the engine compartment
on the driver’s side of the vehicle near the battery.
Lift the cover for access to the fuse/relay block.
To remove fuses hold the end of the fuse between your
thumb and index nger and pull straight out.
SeeEngine Compartment Overview on page 5-14for
more information on its location.
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Page 535 of 594

*1Fuel Injection Rail #2-Gasoline Engine; Engine
Control Module-Diesel Engine.
*2Fuel Injection Rail #1-Gasoline Engine;
Actuator-Diesel Engine.
*3Oxygen Sensors-Gasoline Engine; Fuel Heater-Diesel
Engine.
*4Oxygen Sensors-Gasoline Engine; Engine Control
Module 1-Diesel Engine.
*5Ignition 1-Gasoline Engine; Engine Control
Module-Diesel Engine.
*6Powertrain Control Module B-Gasoline Engine;
Engine Control Module B-Diesel Engine.
*7Rear Climate Control.
*8Sunroof.
Fuses Usage
GLOW PLUGDiesel Glow Plugs and Intake
Air Heater
CUST FEED Gasoline Accessory Power
HYBRID Hybrid
STUD #1Auxiliary Power (Single
Battery and Diesels Only)/
Dual Battery (TP2). Do not
install fuse.
MBECMid Bussed Electrical Center
Power Feed, Front Seats,
Right Doors
Fuses Usage
BLWR Front Climate Control Fan
LBECLeft 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/ECAS Vehicle Stability
IGN A Ignition Power
IGN B Ignition Power
LBEC 1Left Bussed Electrical Center,
Left Doors, Truck Body
Controller, Flasher Module
TRL PARK Parking Lamps Trailer Wiring
RR PARKRight Rear Parking and
Sidemarker Lamps
LR PARKLeft Rear Parking and
Sidemarker Lamps
PARK LP Parking Lamps Relay
STRTR Starter Relay
INTPARK Interior Lamps
STOP LP Stoplamps
TBC BATTTruck Body Controller
Battery Feed
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Fuses Usage
SEO B2 Off-Road Lamps
4WS Not Used
AUX PWRAuxiliary Power
Outlet — Console
PCM 1 Powertrain Control Module
ETC/ECMElectronic Throttle Control,
Electronic Brake
Controller-Gasoline Engine,
Fan Clutch-Diesel Engines
IGN EInstrument Panel Cluster, Air
Conditioning Relay, Turn
Signal/Hazard Switch,
Starter Relay
RTD Ride Control
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 LampsFuses Usage
DRLDaytime Running
Lamps (Relay)
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
RVC Regulated Voltage Control
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 COMPAir Conditioning
Compressor Relay
A/C COMP Air Conditioning Compressor
TCMB Transmission Control Module
RR WPR Not Used
RADIO Audio System
SEO B1Mid Bussed Electrical Center,
Rear Heated Seats,
Universal Home Remote
System
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Fuses Usage
LO HDLP-LT Headlamp Low Beam-Left
BTSIBrake Transmission Shift
Interlock System
CRNK Starting System
LO HDLP-RT Headlamp Low Beam-Right
FOG LP Fog Lamps Relay
FOG LP Fog Lamps
HORN Horn Relay
W/S WASHWindshield Washer
Pump Relay
W/S WASH Windshield Washer Pump
INFOOnStar
®/Rear Seat
Entertainment
RADIO AMP Radio Ampli er
RH HID Not Used
HORN Horn
EAP Not Used
TREC Not Used
SBA Supplemental Brake Assist
Auxiliary Electric Cooling Fan
Fuse Block
The auxiliary electric
cooling fan fuse block is
located in the engine
compartment on the
driver’s side of the vehicle
next to the underhood
fuse block.
Lift the cover for access to the fuse/relay block.
Fuses Usage
COOL/FAN Cooling Fan
COOL/FAN Cooling Fan Relay Fuse
COOL/FAN Cooling Fan Fuse
Relays Usage
COOL/FAN 1 Cooling Fan Relay 1
COOL/FAN 3 Cooling Fan Relay 3
COOL/FAN 2 Cooling Fan Relay 2
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