Page 460 of 674

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.
Trailer Recommendations
You must subtract your hitch loads from the CWR
for your vehicle. Weigh your vehicle with the
trailer attached, so that you won’t go over
the GVWR or GAWR. If you are using a
weight-distributing hitch, weigh the vehicle without
the spring bars in place.
You’ll get the best performance if you spread out
the weight of your load the right way, and if
you choose the correct hitch and trailer brakes.
For more information, seeTowing a Trailer
on page 429.
460
Page 601 of 674
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
4WDFour-Wheel Drive System,
Auxiliary Battery
Fuses Usage
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
601
Page 603 of 674
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 480
for more information on its location.
603
Page 606 of 674

Fuses Usage
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
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 EnginesFuses Usage
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 Lamps
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
606
Page 607 of 674
Fuses Usage
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
SystemFuses 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
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Page 608 of 674
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
608