2002 GMC YUKON XL Owners Manual

4-54When You Are Ready to Leave After
Parking on a Hill 1. Apply your regular brakes and hold the pedal down
while you:

start your engine,

shift into a gear, and

release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer Towing Your vehicle will need service more often when you're
pulling a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transmission fluid (don't
overfill), engine oil, axle lubricant, belt, cooling system
and brake system. Each of these is covered in this
manual, and the Index will help you find them quickly.
If you're trailering, it's a good idea to review these
sections before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight. Trailer Wiring Harness Heavy
- Duty Trailer Wiring Package
Your vehicle is equipped with the seven
- wire trailer
towing harness. This harness with a seven
- pin universal
heavy
- duty trailer connector is attached to a bracket on
the platform hitch.

4-55The 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
A jumper harness for an electric trailer brake controller
and a trailer battery feed fuse are included with this
trailering package. (See ªInstrument Panel Jumper
Wiring Harnessº later in this section.)
If you need to tow a light
- duty trailer with a standard
four
- way round pin connector, an adapter connector is
included with the vehicle. See ªFour
- Wire Trailer
Harness Adapterº later in this section. Instrument Panel Jumper Wiring Harness
This harness is included with the heavy
- duty and
camper/fifth
- wheel trailer wiring packages. The harness
is for an electric trailer brake controller and includes a
trailer battery feed fuse. This harness and fuse should be
installed by your dealer or a qualified service center.

4-56 Four
- Wire Trailer Harness Adapter
If you need to tow a
light
- duty trailer with a
standard four
- way round
pin connector, an adapter
is included.
Connect the adapter with the tab (arrow) pointing
towards the top. The cap on the wiring harness will lock
onto the tab (arrow) and help hold the adapter in place.
Plug the four
- way round pin connector onto the adapter.

5-
5-1Section 5 Problems on the RoadHere you'll find what to do about some problems that can occur on the road.
5
- 2 Hazard Warning Flashers
5
- 2 Other Warning Devices
5
- 3 Jump Starting
5
- 9 Towing Your Vehicle
5
- 9 Engine Overheating
5
- 12 Cooling System 5
- 19 Engine Fan Noise
5
- 19 If a Tire Goes Flat
5
- 20 Changing a Flat Tire
5
- 36 Spare Tire
5
- 37 If You're Stuck: In Sand, Mud, Ice or Snow

5-2Hazard Warning Flashers
Your hazard warning flashers let you warn others. They
also let police know you have a problem. Your front and
rear turn signal lamps will flash on and off.
But they won't flash if you're braking. The hazard warning flasher
button is located at the top
of the steering column.
Press the button to make your front and rear turn signal
lamps flash on and off.
Your hazard warning flashers work no matter what
position your key is in, and even if the key isn't in.
To turn off the flashers, press the button until the first
click and release.
When the hazard warning flashers are on, your turn
signals won't work.
Other Warning Devices If you carry reflective triangles, you can use them to
warn others. Set one up at the side of the road about
300 feet (100 m) behind your vehicle.

5-3Jump Starting If your battery has run down, you may want to
use another vehicle and some jumper cables to start
your vehicle. But please use the following steps to do
it safely.
CAUTION:Batteries can hurt you. They can be
dangerous because:

They contain acid that can burn you.

They contain gas that can explode or ignite.

They contain enough electricity to burn you.
If you don't follow these steps exactly, some or all
of these things can hurt you. NOTICE: Ignoring these steps could result in costly damage
to your vehicle that wouldn't be covered by
your warranty.
The ACDelco 
battery in your vehicle has a
built
- in hydrometer. Do not charge, test or jump
start the battery if the hydrometer looks clear
or light yellow. Replace the battery when there
is a clear or light yellow hydrometer and a
cranking complaint.
Trying to start your vehicle by pushing or pulling
it won't work, and it could damage your vehicle.
1. Check the other vehicle. It must have a 12
- volt
battery with a negative ground system.
NOTICE: If the other system isn't a 12
- volt system with a
negative ground, both vehicles can be damaged.

5-4 2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles aren't touching
each other. If they are, it could cause a ground
connection you don't want. You wouldn't be able to
start your vehicle, and the bad grounding could
damage the electrical systems.
To avoid the possibility of the vehicles rolling, set
the parking brake firmly on both vehicles involved
in the jump start procedure. Put an automatic
transmission in PARK (P) or a manual transmission
in NEUTRAL before setting the parking brake.
NOTICE: If you leave your radio on, it could be badly
damaged. The repairs wouldn't be covered by
your warranty. 3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or accessory power outlets. Turn off the radio
and all lamps that aren't needed. This will avoid
sparks and help save both batteries. And it could
save your radio!
4. Open the hoods and locate the positive (+) and
negative (
- ) terminal locations of the other vehicle.
Your vehicle has a remote positive (+) jump starting
terminal and a remote negative (
- ) jump starting
terminal. You should always use these remote
terminals instead of the terminals on the battery.
The remote positive (+) terminal is located under a
red plastic cover near the engine accessory drive
bracket. To access the remote positive (+) terminal,
open the red plastic cover.
The remote negative (
- ) terminal is located on
the engine accessory drive bracket and is
marked ªGNDº.
See ªEngine Compartment Overviewº in the Index
for more information on location.

5-5CAUTION:Using a match near a battery can cause battery
gas to explode. People have been hurt doing this,
and some have been blinded. Use a flashlight if
you need more light.
Be sure the battery has enough water. You don't
need to add water to the ACDelco

battery
installed in every new GM vehicle. But if a
battery has filler caps, be sure the right amount
of fluid is there. If it is low, add water to take
care of that first. If you don't, explosive gas could
be present.
Battery fluid contains acid that can burn you.
Don't get it on you. If you accidentally get it in
your eyes or on your skin, flush the place with
water and get medical help immediately. 5. Check that the jumper cables don't have loose or
missing insulation. If they do, you could get a shock.
The vehicles could be damaged too.
Before you connect the cables, here are some basic
things you should know. Positive (+) will go to
positive (+) or to a remote positive terminal (+) if the
vehicle has one. Negative (
- ) will go to a heavy,
unpainted metal engine part or to a remote negative
(
- ) terminal, if the vehicle has one.
Don't connect positive (+) to negative (
- ) or you'll
get a short that would damage the battery and maybe
other parts too.
CAUTION: Fans or other moving engine parts can injure you
badly. Keep your hands away from moving parts
once the engine is running.