2003 GMC YUKON roof

When it begins to get dark, the automatic headlamp
system will switch from DRL to the headlamps or the last
chosen headlamp setting that was used.
When you turn the headlamp switch off, the headlamps
will go off, and your DRL lamps will illuminate,
provided it is not dark outside.
Shifting the transmission into PARK (P) will allow you to
idle the vehicle with the DRL off. The DRL will stay
off until you shift the transmission out of PARK (P).
This procedure applies only to vehiclesfirst sold in the
United States.
Fog Lamps
If your vehicle has fog lamps, use them for better vision
in foggy or misty conditions.
The fog lamp button is
located on the left side of
the instrument panel.Your parking lamps and/or low-beam headlamps must
be on for your fog lamps to work.
Press the button to turn the fog lamps on. Press the
button again to turn them off. An indicator light will glow
in the button when the fog lamps are on.
Remember, fog lamps alone will not give off as much
light as your headlamps. Never use your fog lamps
in the dark without turning on your headlamps.
The fog lamps will go off whenever your high-beam
headlamps come on. When the high beams go off, the
fog lamps will come on again.
The fog lamps will be cancelled after the ignition is
turned off. If you still want to use the fog lamps after you
restart the vehicle, you will need to press the fog
lamp button again.
Auxiliary Roof Mounted Lamp Switch
If your vehicle has this feature, this switch includes
wiring provisions for a dealer or a qualified service
center to install an auxiliary roof lamp.
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2003 - Yukon/Yukon XL

This switch is located on
the center of the
instrument panel near the
comfort controls.
When the switch wiring is connected to an auxiliary roof
mounted lamp, pressing the switch will activate the lamp
and illuminate an indicator light near the switch. Pressing
the switch again will turn off the roof mounted lamp.
Interior Lamps
Instrument Panel Brightness
D
:This feature controls the brightness of the
instrument panel lights.
The thumbwheel for this feature is located next to the
headlamp control.Turn the thumbwheel up to adjust the instrument panel
lights. Turn the thumbwheel up to return the radio
display to full brightness when the headlamps or parking
lamps are on. To turn on the dome lamps, turn the
thumbwheel all the way up.
Exit Lighting
With exit lighting, the interior lamps will come on when
you remove the key from the ignition. The lights will
not come on if the dome override button is pressed in.
Entry Lighting
Your vehicle is equipped with an illuminated entry
feature.
When the doors are opened, the dome lamps will come
on if the dome override button is in the out position.
If the dome override button is pressed in, the lamps will
not come on.
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2003 - Yukon/Yukon XL

XM™Satellite Radio Antenna
System (United States Only)
Your XM™Satellite Radio antenna is located on the
roof of your vehicle. Keep this antenna clear of
snow and ice build up for clear radio reception.
The performance of your XM™system may be affected
if your sunroof is open.
Loading items onto the roof of your vehicle can interfere
with the performance of your XM™system. Make
sure that the XM™satellite antenna is not obstructed.
Chime Level Adjustment
The radio is the vehicle chime producer. To change the
volume level, press and hold pushbutton 6 with the
ignition on and the radio power off. The chime volume
level will change from the normal level to loud, and LOUD
will be displayed on the radio. To change back to the
default or normal setting, press and hold pushbutton 6
again. The chime level will change from the loud level to
normal, and NORMAL will be displayed. Each time the
chime volume is changed, three chimes will sound as an
example of the new volume selected. Removing the radio
and not replacing it with a factory radio or chime module
will disable vehicle chimes.
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Before You Go Off-Roading
There are some things to do before you go out. For
example, be sure to have all necessary maintenance and
service work done. Check to make sure all underbody
shields (if so equipped) are properly attached. Be sure
you read all the information about your four-wheel-drive
vehicle in this manual. Is there enough fuel? Is the spare
tire fully inated? Are theuid levels up where they
should be? What are the local laws that apply to
off-roading where you’ll be driving? If you don’t know, you
should check with law enforcement people in the area.
Will you be on someone’s private land? If so, be sure to
get the necessary permission.
Loading Your Vehicle for Off-Road
Driving
There are some important things to remember about
how to load your vehicle.
The heaviest things should be on the loadoor and
forward of your rear axle. Put heavier items as far
forward as you can.
Be sure the load is secured properly, so driving on
the off-road terrain doesn’t toss things around.
{CAUTION:
•Cargo on the loadfloor piled higher than
the seatbacks can be thrown forward
during a sudden stop. You or your
passengers could be injured. Keep cargo
below the top of the seatbacks.
•Unsecured cargo on the loadfloor can be
tossed about when driving over rough
terrain. You or your passengers can be
struck byflying objects. Secure the cargo
properly.
•Heavy loads on the roof raise the vehicle’s
center of gravity, making it more likely to
roll over. You can be seriously or fatally
injured if the vehicle rolls over. Put heavy
loads inside the cargo area, not on the
roof. Keep cargo in the cargo area as far
forward and low as possible.
You’llnd other important information in this manual.
SeeLoading Your Vehicle on page 4-58andTires
on page 5-60.
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Service............................................................5-3
Doing Your Own Service Work.........................5-3
Adding Equipment to the Outside of Your
Vehicle......................................................5-4
Fuel................................................................5-4
Gasoline Octane............................................5-4
Gasoline Specifications....................................5-4
California Fuel...............................................5-5
Additives.......................................................5-5
Fuel E-85 (85% Ethanol).................................5-6
Fuels in Foreign Countries...............................5-7
Filling Your Tank............................................5-7
Filling a Portable Fuel Container.....................5-10
Checking Things Under
the Hood....................................................5-10
Hood Release..............................................5-11
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-16
Engine Air Cleaner/Filter................................5-21
Automatic Transmission Fluid.........................5-23
Engine Coolant.............................................5-26
Coolant Surge Tank Pressure Cap..................5-29Engine Overheating.......................................5-29
Cooling System............................................5-32
Engine Fan Noise.........................................5-37
Power Steering Fluid.....................................5-38
Windshield Washer Fluid................................5-39
Brakes........................................................5-40
Battery........................................................5-43
Jump Starting...............................................5-44
All-Wheel Drive..............................................5-49
Rear Axle.......................................................5-50
Four-Wheel Drive............................................5-51
Front Axle......................................................5-52
Bulb Replacement..........................................5-52
Halogen Bulbs..............................................5-53
Headlamps..................................................5-53
Front Turn Signal, Sidemarker and Daytime
Running Lamps.........................................5-54
Side Identification Marker Lamps.....................5-55
Roof Marker Lamps......................................5-55
Taillamps.....................................................5-57
Replacement Bulbs
.......................................5-59
Section 5 Service and Appearance Care
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2003 - Yukon/Yukon XL

5. Remove the old bulb from the bulb socket.
6. Put the new bulb into the bulb socket. Use care not
to touch the bulb with yourfingers or hands.
7. Put the bulb socket into the turn signal housing and
turn it clockwise until it locks.
8. Put the turn signal housing back onto the vehicle
placing the hook and posts on the inner side into
the alignment holesfirst and then the outer side into
the retainer bracket. Push until you hear a click.
9. Put the headlamp assembly back into the vehicle.
Side Identication Marker Lamps
1. To expose the service slot, locate the lamp gasket
near the rear wheel, and pull back the edge.
2. Using aflat tool, push into the slot to release the
lamp housing.
3. Pull the housing out to expose the wiring harness
and connector.4. Unplug the lamp assembly harness from the
housing.
5. Unplug the lamp.
6. Put in a new lamp and snap it into the housing.
7. Reinstall the lamp housing.
Roof Marker Lamps
1. Remove the
two screws and
lift off the lens.
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2. Remove the six screws on the center roof marker
lamps.
3. Turn the old bulb counterclockwise to remove it
from the socket.4. Put a new bulb into the
socket and turn
clockwise until it locks
in place.
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Replacement Bulbs
Exterior Lamp Bulb Number
Low-Beam Headlamps 9006
High-Beam Headlamps 9005
Daytime Running Lamps (DRL 4114K
Front Roof Marker Lamp 194
Front Parking and Turn Lamp 3457A
Rear Marker Lamp, Taillamp and
Stop Lamp3157
Rear Turn Lamp 3157
Back-up Lamp 3157
For any bulb not listed here contact your dealer.
Windshield Wiper Blade
Replacement
Windshield wiper blades should be inspected at least
twice a year for wear and cracking. SeeAt Least Twice
a Year on page 6-12for more information.
Replacement blades come in different types and are
removed in different ways. For proper type and length,
seeNormal Maintenance Replacement Parts on
page 5-109.To replace the windshield wiper blade assembly do the
following:
1. Lift the wiper arm and turn the blade until it is
facing away from the windshield.
2. Push the release lever and slide the wiper assembly
toward the driver’s side of the vehicle.
3. Install a new blade by reversing Steps 1 and 2.
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