2008 GMC YUKON XL battery

The headphones automatically turn off after four hours
of continuous use.
To adjust the volume on the headphones, use the
volume control located on the right side.
For optimal audio performance, the headphones must
be worn correctly. The symbol L (Left) appears on
the upper left side, above the ear pad and should be
positioned on the left ear. The symbol R (Right) appears
on the upper right side, above the ear pad and should
be positioned on the right ear.
Notice:Do not store the headphones in heat or
direct sunlight. This could damage the headphones
and repairs will not be covered by your warranty.
Storage in extreme cold can weaken the batteries.
Keep the headphones stored in a cool, dry place.
If the foam ear pads attached to the headphones
become worn or damaged, the pads can be replaced
separately from the headphone set. See your
dealer/retailer for more information.Battery Replacement
To change the batteries on the headphones, do the
following:
1. Turn the screw to loosen the battery door located
on the left side of the headphones. Slide the
battery door open.
2. Replace the two batteries in the compartment.
Make sure that they are installed correctly, using
the diagram on the inside of the battery
compartment.
3. Replace the battery door and tighten the
door screw.
If the headphones are to be stored for a long period of
time, remove the batteries and keep them in a cool,
dry place.
3-117

Remote Control
To use the remote control, aim it at the transmitter
window at the rear of the overhead console and press
the desired button. Direct sunlight or very bright light
could affect the ability of the RSE transmitter to receive
signals from the remote control. If the remote control
does not seem to be working, the batteries might need
to be replaced. See “Battery Replacement” later in
this section. Objects blocking the line of sight could also
affect the function of the remote control.
If a CD or DVD is in the Radio DVD slot, the remote
control power button can be used to turn on the video
screen display and start the disc. The radio can also
turn on the video screen display. SeeRadio(s) (MP3) on
page 3-84for more information.
Notice:Storing the remote control in a hot area or
in direct sunlight can damage it, and the repairs
will not be covered by your warranty. Storage
in extreme cold can weaken the batteries. Keep the
remote control stored in a cool, dry place.
Remote Control Buttons
O(Power):Press this button to turn the video screen
on and off.
P(Illumination):Press this button to turn the remote
control backlight on. The backlight automatically
turns off after seven to ten seconds if no other button is
pressed while the backlight is on.
3-120

Battery Replacement
To change the remote control batteries, do the following:
1. Slide the rear cover back on to the remote control.
2. Replace the two batteries in the compartment.
Make sure that they are installed correctly, using
the diagram on the inside of the battery
compartment.
3. Replace the battery cover.
If the remote control is to be stored for a long period of
time, remove the batteries and keep them in a cool,
dry place.
Problem Recommended Action
No power. The ignition might not be
turned ON/RUN or in
ACC/ACCESSORY.
The picture does not ll
the screen. There are
black borders on the
top and bottom or on
both sides or it looks
stretched out.Check the display mode
settings in the setup menu
by pressing the display
menu button on the
remote control.
Problem Recommended Action
In auxiliary mode, the
picture moves or scrolls.Check the auxiliary input
connections at both
devices.
The remote control does
not work.Check to make sure there
is no obstruction between
the remote control and the
transmitter window.
Check the batteries to
make sure they are not
dead or installed
incorrectly.
After stopping the player,
I push Play but sometimes
the DVD starts where I left
off and sometimes at the
beginning.If the stop button was
pressed one time, the
DVD player resumes
playing where the DVD
was stopped. If the stop
button was pressed two
times the DVD player
begins to play from the
beginning of the DVD.
3-123

You can run the engine to keep warm, but be careful.
{CAUTION:
Snow can trap exhaust gases under your
vehicle. This can cause deadly CO (carbon
monoxide) gas to get inside. CO could
overcome you and kill you. You cannot see it
or smell it, so you might not know it is in your
vehicle. Clear away snow from around the
base of your vehicle, especially any that is
blocking the exhaust pipe. And check around
again from time to time to be sure snow does
not collect there.
Open a window just a little on the side of the
vehicle that is away from the wind. This will
help keep CO out.
Run your engine only as long as you must. This saves
fuel. When you run the engine, make it go a little
faster than just idle. That is, push the accelerator
slightly. This uses less fuel for the heat that you get and
it keeps the battery charged. You will need a
well-charged battery to restart the vehicle, and possibly
for signaling later on with the headlamps. Let the
heater run for a while.
4-32

Tow/Haul Mode
Tow/Haul is a feature that assists when pulling a heavy
trailer or a large or heavy load. The purpose of the
Tow/Haul mode is to:
Reduce the frequency and improve the predictability
of transmission shifts when pulling a heavy trailer or
a large or heavy load.
Provide the same solid shift feel when pulling a
heavy trailer or a large or heavy load as when
the vehicle is unloaded.
Improve control of vehicle speed while requiring
less throttle pedal activity when pulling a heavy
trailer or a large or heavy load.
Increase the charging system voltage to assist in
recharging a battery installed in a trailer.Press this button at the end of the shift lever to
enable/disable the tow/haul mode.
A light on the instrument
panel will illuminate to
indicate that tow/haul
mode has been selected.
4-51

Trailer Wiring Harness
Your vehicle is equipped with the following wiring
harnesses for towing a trailer.
Basic Trailer Wiring
The trailer wiring harness, with a seven-pin connector,
is located at the rear of the vehicle and is tied to
the vehicle’s frame. The harness connector can be
plugged into a seven-pin universal heavy-duty trailer
connector available through your dealer/retailer.
The seven-wire harness contains the following trailer
circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Taillamps
White: Ground
Light Green: Back-up Lamps
Red: Battery Feed*
Dark Blue: Trailer Brake*
*The fuses for these two circuits are installed in the
underhood electrical center, but the wires are not
connected. They should be connected by your
dealer/retailer or a qualied service center.
Heavy-Duty Trailer Wiring Harness
Package
Your vehicle is equipped with the seven-wire trailer
towing harness. This harness with a seven-pin universal
trailer connector is attached to a bracket on the hitch
platform.
The seven-wire harness contains the following trailer
circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Taillamps
White: Ground
Light Green: Back-up Lamps
Red: Battery Feed*
Dark Blue: Trailer Brake*
4-62

*The fuses for these two circuits are installed in the
underhood electrical center, but the wires are not
connected. They should be connected by your
dealer/retailer or a qualied service center.
If you are charging a remote (non-vehicle) battery, press
the tow/haul mode button located at the end of the
shift lever. This will boost the vehicle system voltage and
properly charge the battery. If the trailer is too light for
tow/haul mode, you can turn on the headlamps as
a second way to boost the vehicle system and charge
the battery.
Electric Brake Control Wiring
Provisions
These wiring provisions are included with your vehicle
as part of the trailer wiring package. These provisions
are for an electric brake controller. The instrument panel
contains blunt cut wires near the data link connector
for the trailer brake controller. The harness contains the
following wires:
Dark Blue: Brake Signal to Trailer Connector
Red/Black: Battery
Light Blue/White: Brake Switch
White: Ground
It should be installed by your dealer/retailer or a
qualied service center.
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 Cargo
Weight Rating (CWR) for your vehicle. CWR is the
maximum weight of the load your vehicle can carry. It
doesn’t include the weight of the people inside. But you
can gure about 150 lbs. (68 kg) for each seat. The total
cargo load must not be more than your vehicle’s CWR.
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 4-49.
4-63

Service............................................................5-3
Accessories and Modications..........................5-3
California Proposition 65 Warning.....................5-4
California Perchlorate Materials Requirements.....5-4
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside of Your
Vehicle......................................................5-5
Fuel................................................................5-5
Gasoline Octane............................................5-5
Gasoline Specications....................................5-6
California Fuel...............................................5-6
Additives.......................................................5-6
Fuel E85 (85% Ethanol)..................................5-7
Fuels in Foreign Countries...............................5-8
Filling the Tank..............................................5-9
Filling a Portable Fuel Container.....................5-11
Checking Things Under the Hood....................5-12
Hood Release..............................................5-13
Engine Compartment Overview.......................5-14
Engine Oil...................................................5-15
Engine Oil Life System..................................5-18
Engine Air Cleaner/Filter................................5-19
Automatic Transmission Fluid
(4-Speed Transmission)..............................5-22
Automatic Transmission Fluid
(6-Speed Transmission)..............................5-24
Engine Coolant.............................................5-28Coolant Surge Tank Pressure Cap..................5-31
Engine Overheating.......................................5-31
Overheated Engine Protection
Operating Mode........................................5-33
Cooling System............................................5-34
Engine Fan Noise.........................................5-39
Power Steering Fluid.....................................5-39
Windshield Washer Fluid................................5-40
Brakes........................................................5-41
Battery
........................................................5-45
Jump Starting...............................................5-46
Rear Axle.......................................................5-52
Four-Wheel Drive............................................5-54
Front Axle......................................................5-55
Headlamp Aiming...........................................5-56
Bulb Replacement..........................................5-59
Halogen Bulbs..............................................5-59
Taillamps, Turn Signal, Stoplamps and
Back-up Lamps.........................................5-60
License Plate Lamp......................................5-61
Replacement Bulbs.......................................5-61
Windshield Wiper Blade Replacement..............5-62
Tires..............................................................5-64
Tire Sidewall Labeling...................................5-65
Tire Terminology and Denitions.....................5-69
Ination - Tire Pressure.................................5-72
Section 5 Service and Appearance Care
5-1