2003 GMC YUKON DENALI Owners Manual

Contact your dealer to learn how to prepare your
vehicle for longer storage periods.
Also, for your audio system, see Theft-Deterrent
Feature
on page 3-85.
Jump 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.
Notice: Ignoring these steps could result in costly
damage to your vehicle that wouldn’t be covered
by your warranty.
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.
Batteries can hurt you. They can be dangerous
because:
They contain acid that can burn you.
They contain gas that can explode or
They contain enough electricity to burn ignite.
you.
If you don’t follow these steps exactly, some
or all of these things can hurt you.
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Notice: If the other system isn’t a 12-volt system
with a negative ground, both vehicles can be
damaged.
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.
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The remote negative (-)
terminal is located on
the engine accessory
drive bracket and
is
marked GND.
See Engine Compartment Overview on page 5-12
for more information on location. 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 your new 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.
J
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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.
Fans or other moving engine parts can injure
you badly. Keep your hands away from moving
parts once the engine is running.
6. Connect the red
positive
(+) cable to the
positive
(+) terminal of the
dead battery. Use a
remote positive
(+)
terminal if the vehicle
has one.
7. Don’t let the other end
touch metal. Connect it
to the positive
(+)
terminal of the good
battery. Use a remote positive
(+) terminal
if the vehicle has one
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8. Now connect the black
negative
(-) cable to the
negative
(-) terminal
of the good battery. Use
a remote negative
(-)
terminal if the vehicle has
one. Your vehicle’s
remote negative
(-)
terminal is marked GND.
Don’t let the other end touch anything until the next
step. The other end of the negative
(-) cable
doesn’t go to the dead battery.
It goes to a heavy,
unpainted metal engine part or
to a remote
negative
(-) terminal on the vehicle with the
dead battery.
9. Connect the other end of
the negative (-) cable at
least
18 inches (45 cm)
away from the dead
battery, but not near
engine parts that move.
The electrical connection is just as good there, and
the chance of sparks getting back
to the battery
is much less.
10. Now start the vehicle with the good battery and run
the engine for awhile.
11. Try to start the vehicle that had the dead battery. If
it won’t start after a few tries, it probably needs
service.
Notice: Damage to your vehicle may result from
electrical shorting if jumper cables are removed
incorrectly.
To prevent electrical shorting, take care
that the cables don’t touch each other or any
other metal. The repairs wouldn’t be covered by
your warranty.
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A a
Jumper Cable Removal
A. Heavy, Unpainted Metal Engine Part or Remote
B. Good Battery or Remote Positive
(+) and
C. Dead Battery or Remote Positive (+) Terminal.
Negative
(-) Terminal.
Negative
(-) Terminals.
To disconnect the jumper cables from both vehicles do
the following:
1. Disconnect the black negative (-) cable from the
vehicle that had the dead battery.
2. Disconnect the black negative (-) cable from the
3. Disconnect the red positive (+) cable from the
4. Disconnect the red positive (+) cable from the other
5. Return the positive (+) remote terminal cover to its
vehicle
with the good battery.
vehicle with the good battery.
vehicle. original position.
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All-Wheel Drive
Lubricant checks in this section also apply to these
vehicles. However, there are two additional systems that
need lubrication.
Transfer Case
When to Check Lubricant
Refer to the Maintenance Schedule to determine how
often
to check the lubricant. See Part C: Periodic
Maintenance Inspections on page
6-14.
How to Check Lubricant
To get an accurate reading, the vehicle should be on a
level surface.
If the level is below the bottom of the filler plug hole,
you’ll need
to add some lubricant. Add enough lubricant
to raise the level to the bottom of the filler plug hole.
Use care not
to overtighten the plug.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant
to use. See Part D: Recommended
Fluids and Lubricants on page
6-15.
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Front Axle To get an accurate reading, the vehicle should be on a
When to Check and Change Lubricant level surface.
If the level
is below the bottom of the filler plug hole,
Refer to the Maintenance Schedule to determine how
often to check the lubricant and when to change it. See you may need to add
some lubricant.
Part
A: Scheduled Maintenance Services on page 6-4. When the differential is cold, add enough lubricant to
raise the level to 1/2 inch (12 mm) below the filler
How to Check Lubricant plug hole.
When the differential is at operating temperature
(warm), add enough lubricant
to raise the level to the
bottom of the filler plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant
to use. See Part D: Recommended
Fluids and Lubricants on page
6-15.
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