2003 GMC YUKON instrument panel

Some gasolines that are not reformulated for low
emissions may contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. General Motors does not
recommend the use of such gasolines. Fuels containing
MMT can reduce the life of spark plugs and the
performance of the emission control system may be
affected. The malfunction indicator lamp may turn on. If
this occurs, return to your authorized GM dealer for
service.
Fuel E-85 (85% Ethanol)
The 8th digit of your vehicle identification number (VIN)
shows the code letter or number that identifies your
engine. You willfind the VIN at the top left of the
instrument panel. SeeVehicle Identification Number
(VIN) on page 5-96.
If your vehicle has the 5.3L V8 engine (VIN Code Z
only), you may use either regular unleaded gasoline or
ethanol fuel containing up to 85% ethanol (E-85);
also seeFuel on page 5-4. In all other engines, including
the 5.3L V8 (VIN Code T), use only regular unleaded
gasoline.Only vehicles that have the 5.3L V8 engine
(VIN Code Z) may use 85% ethanol fuel (E-85).
Many service stations will not have an 85% ethanol fuel
(E-85) pump available. The U. S. Department of
Energy has an alternative fuels website
(http://afdcmap.nrel.gov/nrel/) that can help youfind
E-85 fuel. Those stations that do have E-85 should have
a label indicating ethanol content. Do not use the fuel
if the ethanol content isgreaterthan 85%. Your vehicle
may not operate properly if the ethanol content is
greater than 85%.
At a minimum, E-85 should meet ASTM
Specification D 5798.
To insure quick starts in the wintertime, the E-85 fuel
must be formulated properly for your climate according
to ASTM specification D 5798. If you have trouble
starting on E-85, it may be because your E-85 fuel is
not properly formulated for your climate. If this happens,
switching to gasoline or adding gasoline to your fuel
tank may improve starting. Your vehicle is designed to
accommodate a mixture of gasoline and E-85 fuel.
For good starting and heater efficiency below 32°F
(0°C), the fuel mix in the fuel tank should contain no
more than 70% ethanol.
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2003 - Yukon/Yukon XL

Coolant Surge Tank Pressure Cap
SeeEngine Compartment
Overview on page 5-12for
more information on
location.
The coolant surge tank pressure cap must be fully
installed on the coolant surge tank.
Notice:Your pressure cap is a pressure-type cap
and must be tightly installed to prevent coolant loss
and possible engine damage from overheating.
See“Capacities and Specications”for more
information.
Engine Overheating
You willfind a coolant temperature gage on your
vehicle’s instrument panel. SeeEngine Coolant
Temperature Gage on page 3-46. In addition, you will
find a LOW COOLANT LEVEL, ENGINE OVERHEATED
and a REDUCED ENGINE POWER message in the
DIC on the instrument panel. SeeDriver Information
Center (DIC) on page 3-53.
Overheated Engine Protection
Operating Mode (V8 Engines Only)
If an overheated engine condition exists and the
REDUCED ENGINE POWER message is displayed, an
overheat protection mode which alternatesfiring
groups of cylinders helps prevent engine damage. In
this mode, you will notice a loss in power and engine
performance. This operating mode allows your vehicle to
be driven to a safe place in an emergency. Driving
extended miles (km) and/or towing a trailer in the
overheat protection mode should be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any repair.
The engine oil will be severely degraded. Repair the
cause of coolant loss, change the oil and reset the oil
life system. See“Engine Oil”in the Index.
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2003 - Yukon/Yukon XL

Cleaning the Top of the Instrument
Panel
Use only mild soap and water to clean the top surfaces
of the instrument panel. Sprays containing silicones
or waxes may cause annoying reflections in the
windshield and even make it difficult to see through the
windshield under certain conditions.
Cleaning Interior Plastic Components
Use only a mild soap and water solution on a soft cloth
or sponge. Commercial cleaners may affect the
surfacefinish.
Cleaning Glass Surfaces
Glass should be cleaned often. GM Glass Cleaner or a
liquid household glass cleaner will remove normal
tobacco smoke and dustfilms on interior glass. SeeGM
Vehicle Care/Appearance Materials on page 5-95.
Notice:Don’t use abrasive cleaners on glass,
because they may cause scratches. Avoid placing
decals on the inside rear window, since they
may have to be scraped off later. If abrasive cleaners
are used on the inside of the rear window, an
electric defogger element may be damaged. Any
temporary license should not be attached across the
defogger grid.
Care of Safety Belts
Keep belts clean and dry.
{CAUTION:
Do not bleach or dye safety belts. If you do, it
may severely weaken them. In a crash, they
might not be able to provide adequate
protection. Clean safety belts only with mild
soap and lukewarm water.
Weatherstrips
Silicone grease on weatherstrips will make them last
longer, seal better, and not stick or squeak. Apply
silicone grease with a clean cloth at least every six
months. During very cold, damp weather more frequent
application may be required. SeePart D: Recommended
Fluids and Lubricants on page 6-17.
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2003 - Yukon/Yukon XL

GM Vehicle Care/Appearance Materials
(cont’d)
Description Usage
Wash Wax ConcentrateMedium foaming
shampoo. Cleans and
lightly waxes.
Biodegradable and
phosphate free.
Spot LifterQuickly and easily
removes spots and stains
from carpets, vinyl and
cloth upholstery.
Odor EliminatorOdorless spray odor
eliminator used on
fabrics, vinyl, leather and
carpet.
See your General Motors parts department for these
products. SeePart D: Recommended Fluids and
Lubricants on page 6-17.
Vehicle Identication
Vehicle Identication Number (VIN)
This is the legal identifier for your vehicle. It appears on
a plate in the front corner of the instrument panel, on
the driver’s side. You can see it if you look through the
windshield from outside your vehicle. The VIN also
appears on the Vehicle Certification and Service Parts
labels and the certificates of title and registration.
Engine Identication
The 8th character in your VIN is the engine code. This
code will help you identify your engine, specifications
and replacement parts.
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2003 - Yukon/Yukon XL

Fuses and Circuit Breakers
The wiring circuits in your vehicle are protected from
short circuits by a combination of fuses, circuit breakers
and fusible thermal links. This greatly reduces the
chance offires caused by electrical problems.
Look at the silver-colored band inside the fuse. If the
band is broken or melted, replace the fuse. Be sure you
replace a bad fuse with a new one of the identical
size and rating.
If you ever have a problem on the road and don’t have
a spare fuse, you can borrow one that has the same
amperage. Just pick some feature of your vehicle
that you can get along without–like the radio or
cigarette lighter–and use its fuse, if it is the correct
amperage. Replace it as soon as you can.
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.
To remove fuses, hold the end of the fuse between your
thumb and indexfinger and pull straight out.
You may have spare fuses located behind the fuse
block access door. These can be used to replace a bad
fuse. However, make sure it is of the correct amperage.
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2003 - Yukon/Yukon XL

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.
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*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
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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
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2003 - Yukon/Yukon XL