2003 GMC YUKON trailer

Fuses Usage
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
AUX PWR 2Rear Cargo Area Power
Outlets
LOCKS Power Door Lock System
ECCRear Electronic Climate
Control
TBC 2C Truck Body Controller
FLASH Flasher Module
CB LT DOORSLeft Power Window Circuit
Breaker
TBC 2B Truck Body Controller
TBC 2A Truck Body ControllerCenter Instrument Panel Fuse Block
The center instrument panel utility block is located
underneath the instrument panel, to the left of the
steering column.
5-100
2003 - Yukon/Yukon XL

Device Usage
SEO Special Equipment Option
TRAILER Trailer Brake Wiring
UPFIT Upfitter (Not Used)
SL RIDERide Control Harness
Connection
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 Window 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 indexfinger and pull straight out.
5-101
2003 - Yukon/Yukon XL

*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—PCM Ignition
Fuses Usage
GLOW PLUG Not Used
CUST FEED Gasoline Accessory Power
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
BLOWER Front Climate Control Fan
LBECLeft Bussed Electrical Center,
Door Modules, Door Locks,
Auxiliary Power Outlet—Rear
Cargo Area and Instrument
Panel
STUD 2Accessory Power/Trailer
Wiring Brake Feed
ABS Anti-Lock Brakes
Fuses Usage
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
STARTER Starter Relay
INTPARK Interior Lamps
STOP LP Stoplamps
TBC BATTTruck Body Controller Battery
Feed
SUNROOF Sunroof
SEO B2 Off-Road Lamps
4WSVent Solenoid
Canister/Quadrasteer Module
Power
RR HVAC Rear Climate Control
5-103
2003 - Yukon/Yukon XL

Fuses Usage
AUX PWRAuxiliary Power
Outlet—Console
IGN 1 Ignition Relay
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
RTD Ride Control
TRL B/U Backup Lamps Trailer Wiring
PCM BPowertrain Control Module,
Fuel Pump
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
SIRSupplemental Inflatable
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
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 COMP Air Conditioning Compressor
A/C COMPAir Conditioning Compressor
Relay
RR WPR Rear Wiper/Washer
5-104
2003 - Yukon/Yukon XL

50,000 Miles (83 000 km)
❑Change automatic transmissionfluid andfilter if the
vehicle’s GVWR is over 8600 lbs or if the vehicle is
mainly driven under one or more of these conditions:
In heavy city traffic where the outside
temperature regularly reaches 90°F (32°C) or
higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or delivery
service.
If you do not use your vehicle under any of these
conditions, change the fluid and filter at 100,000 miles
(166 000 km).
❑Change transfer case uid.
52,500 Miles (87 500 km)
❑Check rear/front axle uid level and add uid as
needed. Check constant velocity joints and axle seals
for leaking.
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-61for proper rotation pattern and additional
information.(See footnote +.)
60,000 Miles (100 000 km)
❑Check rear/front axle uid level and add uid as
needed. Check constant velocity joints and axle seals
for leaking.
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-61for proper rotation pattern and additional
information.(See footnote +.)
❑Replace fuel lter.An Emission Control Service.
(See footnote †.)
❑Replace engine air cleaner lter on vehicles without
a restriction indicator. If equipped with a change
indicator, inspect the indicator. If necessary, replace
the lter. If vehicle is driven in dusty/dirty conditions,
inspect the change indicator (if equipped) at every
engine oil change. SeeEngine Air Cleaner/Filter on
page 5-21for more information.An Emission
Control Service. (See footnote †.)
❑Inspect Evaporative Control System. Check all fuel
and vapor lines and hoses for proper hook-up,
routing and condition. Check that the purge valve
works properly, if equipped. Replace as needed.An
Emission Control Service. (See footnote †.)
6-8
2003 - Yukon/Yukon XL

97,500 Miles (162 500 km)
❑Check rear/front axleuid level and adduid as
needed. Check constant velocity joints and axle seals
for leaking.
❑Rotate tires. SeeTire Inspection and Rotation on
page 5-61for proper rotation pattern and additional
information.(See footnote +.)
100,000 Miles (166 000 km)
❑Inspect spark plug wires.An Emission Control
Service.
❑Replace spark plugs.An Emission Control Service.
❑Change automatic transmissionuid andlter if
the vehicle’s GVWR is over 8,600 lbs or if the vehicle
is mainly driven under one or more of these
conditions:
In heavy city traffic where the outside
temperature regularly reaches 90°F (32°C) or
higher.
In hilly or mountainous terrain.When doing frequent trailer towing.
Uses such as found in taxi, police or delivery
service.
❑If you haven’t used your vehicle under severe service
conditions listed previously and, therefore, haven’t
changed your automatic transmissionuid, change
both theuid andlter.
❑Change transfer caseuid.
❑Except 8.1L V8 Engine: Inspect Positive Crankcase
Ventilation (PCV) valve.An Emission Control
Service.
150,000 Miles (240 000 km)
❑Drain,ush and rell cooling system (or every
60 months since last service, whichever occursrst).
SeeEngine Coolant on page 5-26for what to use.
Inspect hoses. Clean radiator, condenser, pressure
cap and neck. Pressure test the cooling system
and pressure cap.An Emission Control Service.
❑Inspect engine accessory drive belt.An Emission
Control Service.
6-10
2003 - Yukon/Yukon XL

D
Daytime Running Lamps..................................3-16
Defensive Driving............................................. 4-2
Defogging and Defrosting.........................3-24, 3-30
Delayed Locking............................................... 2-9
Dinghy Towing................................................4-55
Doing Your Own Service Work........................... 5-3
Dolly Towing..................................................4-57
Dome Lamps .................................................3-20
Door
Delayed Locking........................................... 2-9
Locks.......................................................... 2-7
Power Door Locks......................................... 2-8
Programmable Automatic Door Locks............... 2-9
Rear Door Security Locks.............................2-11
Driver
Position, Safety Belt.....................................1-28
DRIVER DOOR AJAR.....................................3-69
Driver Information Center (DIC).........................3-53
DIC Operation and Displays..........................3-54
DIC Warnings and Messages........................3-64
Driving
At Night
.....................................................4-37
City
...........................................................4-42Driving (cont.)
Defensive..................................................... 4-2
Drunken....................................................... 4-2
Freeway.....................................................4-43
Hill and Mountain Roads..............................4-45
In Rain and on Wet Roads...........................4-39
Winter........................................................4-47
Driving Across an Incline..................................4-33
Driving Downhill..............................................4-32
Driving in Mud, Sand, Snow or Ice....................4-35
Driving in Water..............................................4-36
Driving On Grades..........................................4-70
Driving on Off-Road Hills.................................4-28
Driving on Snow or Ice....................................4-48
Driving Through Deep Standing Water...............4-40
Driving Through Flowing Water.........................4-41
Driving Uphill..................................................4-29
Driving with a Trailer.......................................4-68
Dual Automatic Climate Control System.............3-26
Dual Climate Control System............................3-22
DVD
Cleaning the Video Screen..........................3-125
Distortion..................................................3-123
Rear Seat Entertainment System..................3-111
DVD Player..................................................3-111
5
2003 - Yukon/Yukon XL

H
Hazard Warning Flashers................................... 3-6
Head Restraints............................................... 1-8
Headlamp High/Low-Beam Changer.................... 3-9
Headlamps....................................................5-53
Bulb Replacement.......................................5-52
Front Turn Signal, Sidemarker and Daytime
Running Lamps........................................5-54
Halogen Bulbs............................................5-53
Roof Marker Lamps.....................................5-55
Side Identification Marker Lamps...................5-55
Headphones.................................................3-117
Heated Seats................................................... 1-5
Heating.........................................................3-30
Highway Hypnosis...........................................4-44
Hill and Mountain Roads..................................4-45
Hitches..........................................................4-67
HomeLink Transmitter, Programming..................2-51
HomeLink
®Transmitter....................................2-50
Hood
Checking Things Under................................5-10
Release.....................................................5-11
Horn ............................................................... 3-7
How to Add Coolant to the Coolant Surge Tank......5-34
How to Add Fluid
............................................5-25
How to Check
........................................5-23, 5-61
How to Check Lubricant
...................................5-50How to Check Power Steering Fluid..................5-39
How to Inspect...............................................5-21
How to Use This Manual...................................... ii
How to Wear Safety Belts Properly...................1-27
Hydroplaning..................................................4-40
I
If No Steam Is Coming From Your Engine..........5-31
If Steam Is Coming From Your Engine...............5-30
If the Light is Flashing.....................................3-49
If the Light Is On Steady.................................3-49
If You Are Stuck in Sand, Mud, Ice or Snow.......4-52
If You Do Decide To Pull A Trailer.....................4-62
If You’re Caught in a Blizzard...........................4-50
Ignition Positions.............................................2-19
Ignition Transmission Lock Check......................6-14
Infants and Young Children, Restraints...............1-46
Inflation -- Tire Pressure..................................5-61
Inspection
Brake System.............................................6-16
Engine Cooling System................................6-16
Exhaust System..........................................6-15
Fuel System...............................................6-15
Part C - Periodic Maintenance.......................6-15
Steering and Suspension..............................6-15
Transfer Case and Front Axle
(Four-Wheel Drive)...................................6-16
8
2003 - Yukon/Yukon XL