2003 GMC YUKON DENALI Owners Manual

Starting and Operating Your
Vehicle
New Vehicle Break-In
Notice: Your vehicle doesn’t need an elaborate
“break-in.’’ But
it will perform better in the long run
if you follow these guidelines:
e
e
Keep your speed at 55 mph (88 km/h) or less for
the first
500 miles (805 km).
Don’t drive at any one speed
- fast or
slow
- for the first 500 miles (805 km).
Don’t make full-throttle starts.
Avoid making hard stops for the first
200 miles
(322 km) or so. During this time your new
brake linings aren’t yet broken in. Hard stops
with new linings can mean premature wear and
earlier replacement. Follow this breaking-in
guideline every time you get new brake linings.
Don’t tow a trailer during break-in. See “Towing
a Trailer” in the Index for more information.
Ignition Positions
With your key in the ignition switch you can turn it to
four different positions.
I C
A-
A (LOCK): This position locks your ignition and
transmission. It’s a theft-deterrent feature. You
will only
be able
to remove your key when the ignition is
turned to
LOCK.
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Notice: If your key seems stuck in LOCK and you
can’t turn
it, be sure you are using the correct key; if
so, is it all the way in? Turn the key only with
your hand. Using a tool to force
it could break the
key or the ignition switch.
If none of these works,
then your vehicle needs service.
B (ACCESSORY): This position allows you to use
things like the radio, power windows and the windshield
wipers when the engine is
off.
C (RUN): This position is for driving.
D (START): This position starts your engine.
Retained Accessory Power (RAP)
The Retained Accessory Power (RAP) feature will
allow certain features on your vehicle
to continue to
work for up
to 10 minutes after the ignition key is turned
to LOCK.
Starting Your Engine
Move your shift lever to PARK (P) or NEUTRAL (N).
Your engine won’t start in any other position - that’s a
safety feature. To restart when you’re already moving,
use NEUTRAL
(N) only.
Notice: Don’t try to shift to PARK (P) if your
vehicle
is moving. If you do, you could damage the
transaxle. Shift
to PARK (P) only when your
vehicle
is stopped.
1. With your foot
off the accelerator pedal, turn the
ignition key
to START. When the engine starts,
let go of the key. The idle speed will go down as
your engine gets warm.
Notice: Holding your key in START for longer than
15 seconds at a time will cause your battery to
be drained much sooner. And the excessive heat
can damage your starter motor. Wait about
15
seconds between each try to help avoid draining
your battery or damaging your starter.
2. If it doesn’t start within 10 seconds, push the
accelerator pedal all the way
to the floor, while you
hold the ignition key in START. When the engine
starts, let go of the key and let up on the accelerator
pedal. Wait about
15 seconds between each try.
When starting your engine in very cold weather
(below
0°F or -18”C), do this:
1. With your foot off the accelerator pedal, turn the
ignition key to START and hold it there up
to
15 seconds. When the engine starts, let go of
the key.
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2. If your engine still won’t start (or starts but then
stops), it could be flooded with too much gasoline.
Try pushing your accelerator pedal all the way to the
floor and holding it there as you hold the key in START for about three seconds. When the engine
starts, let go of the key and accelerator. If the
vehicle starts briefly but then stops again, do the
same thing, but this time keep the pedal down
for five or six seconds. This clears the extra
gasoline from the engine.
Notice: Your engine is designed to work with the
electronics in your vehicle.
If you add electrical
parts or accessories, you could change the way the
engine operates. Before adding electrical equipment,
check with your dealer. If you don’t, your engine
might not perform properly.
Adjustable Throttle and Brake Pedal
If your vehicle has this feature, you can change the
position of the throttle and brake pedals. This feature is
designed for shorter drivers, since the pedals cannot
move farther away from the standard position, but can
move forward for better pedal reach. This feature
can be programmed to work with the memory function
(if equipped) on your vehicle. See Memory Seat on
page 2-47.
The vehicle must be in PARK (P) for this feature to
operate.
The buttons used to adjust
the pedals are located on
the driver’s side door panel.
Press the button closest to you to move the pedals
closer to your body. Press the button farthest from you
to move the pedals away from your body.
2-20

Engine Coolant Heater
Your vehicle may be equipped with an engine
coolant heater.
I
Usually, the coolant heater sho In very cold weather,
0°F
(-18°C) or
colder, the
engine coolant heater can
help. You’ll get easier
starting and better
fuel economy during
engine warm-up.
luld be ph Jgged in a
minimum of four hours prior to starting your vehicle.
At temperatures above 32°F (OOC), use of the coolant
heater is not required.
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord.
The cord is located on the driver’s side of the
engine compartment, near the power steering
fluid reservoir. 3.
Plug it into a normal, grounded 1 IO-volt AC outlet.
PIL,ging the cord inl, an ,..grc,.lded out.,_
could cause an electrical shock. Also, the
wrong kind
of extension cord could overheat
and cause a fire. You could be seriously
injured. Plug the cord into a properly grounded
three-prong
11 0-volt AC outlet. If the cord
won’t reach, use a heavy-duty three-prong
extension cord rated for at least
15 amps.
4. Before starting the engine, be sure to unplug and
store the cord as it was before to keep it away
from moving engine parts.
If you don’t, it could be
damaged.
How long should you keep the coolant heater plugged
in? The answer depends on the outside temperature, the
kind of oil you have, and some other things. Instead
of trying to list everything here, we ask that you contact
your dealer in the area where you’ll be parking your
vehicle. The dealer can give you the best advice for that
particular area.
2-21

Automatic Transmission Operation
Your vehicle is equipped with an automatic transmission
and features an electronic shift position indicator
located within the instrument panel cluster.
There are several different positions for your shift lever.
PARK
(P): This position locks your drive wheels. It’s
the best position to use when you start your engine
because your -1icle
c ’t move easily.
It is aangerous to get out of your venlcle il
shift lever is not fully in PARK (P) with the
parking brake firmly set. Your vehicle can roll.
Don’t leave your vehicle when the engine is
running unless you have to.
If you have left the
engine running, the vehicle can move
suddenly. You or others could be injured.
CAUTION: (Continued)
o be sure your vehicle won’t move, even
when you’re on fairly level ground, always set
your parking brake and move the shift lever to PARK (P). See “Shifting Into Park (P)” in the
Index.
If you’re pulling a trailer, see “Towing a
Trailer” in the Index.
REVERSE (R): Use this gear to back up.
Notices Shifting to REVERSE (R) while your vehicle
is moving forward could damage your transmission.
Shift to REVERSE
(R) only after your vehicle is
stopped.
To rock your vehicle back and forth to get out of snow,
ice or sand without damaging your transmission,
see If
You Are Stuck: In Sand, Mud, Ice or Snow on
page 4-4 1.
NEUTRAL (N): In this position, your engine doesn’t
connect with the wheels. To restart when you’re already
moving, use NEUTRAL
(N) only.
2-22

Shifting into a drive gear while your engine is
“racing” (running at high speed) is dangerous.
Unless your foot is firmly on the brake pedal,
your vehicle could move very rapidly. You
could lose control and hit people or objects.
Don’t shift into a drive gear while your engine
is racing.
Notices Damage to your transmission caused by
shifting out of PARK (P) or NEUTRAL (N) with
the engine racing isn’t covered by your warranty.
DRIVE (D):
This position is for normal driving. If
you need more power for passing, and you’re:
accelerator pedal about halfway down.
accelerator all the way down.
0 Going less than about 35 mph (55 km/h), push your
Going about 35 mph (55 km/h) or more, push the
You’ll shift down
to the next gear and have more power.
DRIVE (D) can be used when towing a trailer, carrying
a heavy load, driving on steep hills or for off-road driving.
You may want
to shift the transmission to THIRD (3)
or, if necessary, a lower gear selection if the
transmission shifts
too often.
THIRD (3): This position is also used for normal driving,
however it offers more power and lower fuel economy
than DRIVE (D).
SECOND (2): This position gives you more power but
lower fuel economy. You can use SECOND
(2) on
hills.
It can help control your speed as you go down
steep mountain roads, but then you would also want
to
use your brakes off and on.
If you manually select SECOND
(2), the transmission
will drive in second gear. You may use this feature
for reducing the speed of the rear wheels when you are
trying
to start your vehicle from a stop on slippery
road surfaces. Once the vehicle
is moving, shift into
DRIVE
(D).
FIRST (1): This position gives you even more power,
but lower fuel economy than SECOND
(2). You can use
it on very steep hills, or in deep snow or mud. If the
shift lever is put in FIRST
(1) while the vehicle is moving
forward, the vehicle won’t shift into first gear until the
vehicle is going slowly enough.
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Notice: If your wheels won’t turn, don’t try to drive.
This might happen
if you were stuck in very deep
sand or mud or were up against
a solid object. You
could damage your transmission. Also, if you
stop when going uphill, don’t hold your vehicle there
with only the accelerator pedal. This could overheat
and damage the transmission. Use your brakes
or shift into
PARK (P) to hold your vehicle in
position on
a hill.
On cold days, approximately
32°F (OOC) or colder, your
transmission is designed
to shift differently until the
engine reaches normal operating temperature. This is
intended
to improve heater performance.
Tow/HauI Mode
Your vehicle is equipped with a tow/haul mode. The
button is located on the end
of the column shift lever.
You can use this feature
to assist when towing or
hauling a heavy load. See “Tow/Haul Mode” under
Towing
a Trailer on page 4-47 for more information.
The tow/haul mode also interacts with the AutorideTM
feature
to enhance the ride when trailering or with
a loaded vehicle. See AutorideTM on page
4-46.
2-24

Parking Brake
To set the parking brake, hold the regular brake pedal
down with your right foot. Push down the parking
brake pedal with your left foot.
A chime will activate and the warning light will flash
when the parking brake is applied and the vehicle
is moving at
least 3 mph (5 km/h) for at least three
seconds.
To release the parking brake, hold the regular brake
pedal down.
Pull the bottom edge of the lever, located
above the parking brake pedal, with the parking
brake symbol,
to release the parking brake.
If the ignition is on when the parking brake is releasea,
the brake system warning light will go
off.
Notice: Driving with the parking brake on can
cause your rear brakes to overheat. You may have
to replace them, and you could also damage
other parts
of your vehicle.
If you are towing a trailer and are parking on any hill,
see Towing a Trailer on page
4-47.
2-25