warning GMC YUKON DENALI 2010 Repair Manual

C (ON/RUN) :This position can be used to operate the
electrical accessories and to display some instrument
panel cluster warning and indicator lights. The switch
stays in this position when the engine is running.
The transmission is also unlocked in this position on
automatic transmission vehicles.
If you leave the key in the ACC/ACCESSORY or
ON/RUN position with the engine off, the battery could
be drained. You may not be able to start the vehicle if
the battery is allowed to drain for an extended period
of time.
D (START) : This is the position that starts the engine.
When the engine starts, release the key. The ignition
switch returns to ON/RUN for driving.
A warning tone will sound when the driver door is
opened, the ignition is in ACC/ACCESSORY or
LOCK/OFF and the key is in the ignition.Retained Accessory Power (RAP)
The following vehicle accessories can be used for up to
10 minutes after the engine is turned off:
.Audio System
.Power Windows
.OnStar®System (if equipped)
.Sunroof (if equipped)
These features work when the key is in ON/RUN or
ACC/ACCESSORY. Once the key is turned from
ON/RUN to LOCK/OFF, the windows and sunroof
continue to work up to 10 minutes until any door is
opened. The radio continues to work for up to
10 minutes or until the driver door is opened.
Starting the Engine
Move the shift lever to P (Park) or N (Neutral).
The engine will not start in any other position.
To restart the engine when the vehicle is already
moving, use N (Neutral) only.
Notice: Do not try to shift to P (Park) if the vehicle
is moving. If you do, you could damage the
transmission. Shift to P (Park) only when the
vehicle is stopped.
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3. Plug the cord into a normal, grounded 110-voltAC outlet.
{WARNING:
Plugging the cord into an ungrounded outlet 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 110-volt AC
outlet. If the cord will not 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 do not, it could be
damaged.
The length of time the heater should remain plugged in
depends on several factors. Ask a dealer/retailer in the
area where you will be parking the vehicle for the best
advice on this.
Active Fuel Management™
Vehicles with V8 engines may have Active Fuel
Management™. This system allows the engine to
operate on either all or half of its cylinders, depending
on the driving conditions.
When less power is required, such as cruising at a
constant vehicle speed, the system will operate in the
half cylinder mode, allowing the vehicle to achieve
better fuel economy. When greater power demands are
required, such as accelerating from a stop, passing,
or merging onto a freeway, the system will maintain
full-cylinder operation.
If the vehicle has an Active Fuel Management™
indicator, see DIC Operation and Displays (Using DIC
Buttons)
on page 4‑43or DIC Operation and Displays
(Using Trip Odometer Reset Stem)on page 4‑50for
more information on using this display .
3-29

Automatic Transmission Operation
The vehicle has a Hydra-Matic®6L80 automatic
transmission, and has an electronic shift position
indicator within the instrument panel cluster.
The electronic shift position indicator displays when
the shift lever is moved out of P (Park).
There are several different positions for the shift lever.
Light Duty 6‐Speed Automatic Transmission Shown (Heavy Duty 6‐Speed Similar)
See “Range Selection Mode” later in this section.
P (Park) : This position locks your rear wheels. It is the
best position to use when you start the engine because
the vehicle cannot move easily. When parked on a hill, especially when the vehicle has
a heavy load, you may notice an increase in the effort
to shift out of P (Park). See Torque Lock (Automatic
Transmission) under
Shifting Into Park
on page 3‑37for more information.
{WARNING:
It is dangerous to get out of the vehicle if the shift
lever is not fully in P (Park) with the parking brake
firmly set. The vehicle can roll.
Do not leave the 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. To be sure the
vehicle will not move, even when you are on fairly
level ground, always set the parking brake and
move the shift lever to P (Park). See Shifting Into
Park
on page 3‑37. If you are pulling a trailer,
see Towing a Trailer on page 5‑42.
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R (Reverse) :Use this gear to back up.
Notice: Shifting to R (Reverse) while the vehicle is
moving forward could damage the transmission.
The repairs would not be covered by the vehicle
warranty. Shift to R (Reverse) only after the vehicle
is stopped.
To rock the vehicle back and forth to get out of snow,
ice, or sand without damaging the transmission, see If
Your Vehicle is Stuck in Sand, Mud, Ice, or Snow
on
page 5‑29.
N (Neutral) : In this position, the engine does not
connect with the wheels. To restart the engine when the
vehicle is already moving, use N (Neutral) only. Also,
use N (Neutral) when the vehicle is being towed.
{WARNING:
Shifting into a drive gear while the engine is
running at high speed is dangerous. Unless your
foot is firmly on the brake pedal, the vehicle could
move very rapidly. You could lose control and hit
people or objects. Do not shift into a drive gear
while the engine is running at high speed. Notice:
Shifting out of P (Park) or N (Neutral) with
the engine running at high speed may damage the
transmission. The repairs would not be covered by
the vehicle warranty. Be sure the engine is not
running at high speed when shifting the vehicle.
D (Drive) : This position is for normal driving. It provides
the best fuel economy for the vehicle. If you need more
power for passing, and you are:
.Going less than about 35 mph (55 km/h), push the
accelerator pedal about halfway down.
.Going about 35 mph (55 km/h) or more, push the
accelerator all the way down.
D (Drive) 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 a lower gear
selection if the transmission shifts too often.
Downshifting the transmission in slippery road
conditions could result in skidding, see “Skidding”
under Loss of Control on page 5‑11.
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Parking Brake
Set the parking brake by holding the regular brake
pedal down, then pushing down the parking brake
pedal.If the ignition is on, the brake system warning light
will come on. See
Brake System Warning Light
on
page 4‑32.
Notice: Driving with the parking brake on can
overheat the brake system and cause premature
wear or damage to brake system parts. Make sure
that the parking brake is fully released and the
brake warning light is off before driving.
To release the parking brake, hold the regular brake
pedal down, then push down momentarily on the
parking brake pedal until you feel the pedal release.
Slowly pull your foot up off the park brake pedal. If the
parking brake is not released when you begin to drive,
the brake system warning light will flash and a chime
will sound warning you that the parking brake is still on.
If you are towing a trailer and are parking on a hill,
see Towing a Trailer on page 5‑42.
3-36

Shifting Into Park
{WARNING:
It can be dangerous to get out of the vehicle if the
shift lever is not fully in P (Park) with the parking
brake firmly set. The vehicle can roll. If you have
left the engine running, the vehicle can move
suddenly. You or others could be injured. To be
sure the vehicle will not move, even when you are
on fairly level ground, use the steps that follow.
If you are pulling a trailer, seeTowing a Trailer
on
page 5‑42
.
1. Hold the brake pedal down, then set the parking brake.
2. Move the shift lever into the P (Park) position by pulling the shift lever toward you and moving it up
as far as it will go.
3. Turn the ignition key to LOCK/OFF.
4. Remove the key and take it with you. If you can leave the vehicle with the ignition key in your hand,
the vehicle is in P (Park).
Leaving the Vehicle With the Engine
Running
{WARNING:
It can be dangerous to leave the vehicle with the
engine running. The vehicle could move suddenly
if the shift lever is not fully in P (Park) with the
parking brake firmly set. And, if you leave the
vehicle with the engine running, it could overheat
and even catch fire. You or others could be
injured. Do not leave the vehicle with the engine
running.
If you have to leave the vehicle with the engine running,
be sure the vehicle is in P (Park) and the parking brake
is firmly set. After the shift lever is moved into P (Park),
hold the regular brake pedal down. Then, see if you can
move the shift lever away from P (Park) without first
pulling it toward you. If you can, it means that the shift
lever was not fully locked into P (Park).
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To shift out of P (Park) use the following:1. Apply the brake pedal.
2. Move the shift lever to the desired position.
If you still are unable to shift out of P (Park): 1. Ease the pressure on the shift lever.
2. While holding down the brake pedal, press the shift lever all the way into P (Park).
3. Move the shift lever to the desired position.
If you are still having a problem shifting, then have the
vehicle serviced soon.Parking Over Things That Burn
{WARNING:
Things that can burn could touch hot exhaust
parts under the vehicle and ignite. Do not park
over papers, leaves, dry grass, or other things that
can burn.
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Engine Exhaust
{WARNING:
Engine exhaust contains Carbon Monoxide (CO)
which cannot be seen or smelled. Exposure to CO
can cause unconsciousness and even death.
Exhaust may enter the vehicle if:
.The vehicle idles in areas with poor ventilation
(parking garages, tunnels, deep snow that
may block underbody airflow or tail pipes).
.The exhaust smells or sounds strange or
different.
.The exhaust system leaks due to corrosion or
damage.
.The vehicle’s exhaust system has been
modified, damaged or improperly repaired.
.There are holes or openings in the vehicle
body from damage or after-market
modifications that are not completely sealed.(Continued)
WARNING: (Continued)
If unusual fumes are detected or if it is suspected
that exhaust is coming into the vehicle:
.Drive it only with the windows
completely down.
.Have the vehicle repaired immediately.
Never park the vehicle with the engine running in
an enclosed area such as a garage or a building
that has no fresh air ventilation.
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Running the Vehicle While Parked
It is better not to park with the engine running. But if you
ever have to, here are some things to know.
{WARNING:
Idling a vehicle in an enclosed area with poor
ventilation is dangerous. Engine exhaust may
enter the vehicle. Engine exhaust contains
Carbon Monoxide (CO) which cannot be seen or
smelled. It can cause unconsciousness and
even death. Never run the engine in an enclosed
area that has no fresh air ventilation. For more
information, seeEngine Exhaust on page 3‑40.
{WARNING:
It can be dangerous to get out of the vehicle if the
automatic transmission shift lever is not fully in
P (Park) with the parking brake firmly set. The
vehicle can roll. Do not leave the 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. To be
sure the vehicle will not move, even when you are
on fairly level ground, always set the parking
brake and move the shift lever to P (Park).
Follow the proper steps to be sure the vehicle will not
move. See Shifting Into Park on page 3‑37.
If parking on a hill and pulling a trailer, see Towing a
Trailer on page 5‑42.
3-41

Park Tilt Mirrors
If the vehicle has the memory package, the passenger
and/or driver mirror tilts to a preselected position when
the vehicle is in R (Reverse). This feature lets the driver
view the curb when parallel parking. The mirror(s) return
to the original position when the vehicle is shifted out of
R (Reverse), or the ignition is turned off or to
OFF/LOCK.
Turn this feature on or off through the Driver Information
Center (DIC). SeeDIC Vehicle Customization (With DIC
Buttons)
on page 4‑66for more information.
Outside Convex Mirror
{WARNING:
A convex mirror can make things, like other
vehicles, look farther away than they really are.
If you cut too sharply into the right lane, you could
hit a vehicle on the right. Check the inside mirror
or glance over your shoulder before changing
lanes. The passenger side mirror is convex shaped. A convex
mirror's surface is curved so more can be seen from the
driver seat.
Outside Heated Mirrors
<(Rear Window Defogger):
Press to heat the
mirrors.
See “Rear Window Defogger” underDual Automatic
Climate Control System
on page 4‑18for more
information.
Side Blind Zone Alert (SBZA)
If the vehicle has the Side Blind Zone Alert (SBZA)
system, see Side Blind Zone Alert (SBZA)on
page 3‑47for more information.
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