2010 GMC SIERRA DENALI lock

Starting Procedure
1. With your foot off the accelerator pedal, turn theignition to START. When the engine starts, let go of
the key. The idle speed will slow down as the
engine warms. Do not race the engine immediately
after starting it. Operate the engine and
transmission gently to allow the oil to warm up and
lubricate all moving parts.
The vehicle has a Computer-Controlled Cranking
System. This feature assists in starting the engine
and protects components. If the ignition key is
turned to the START position, and then released
when the engine begins cranking, the engine will
continue cranking for a few seconds or until the
vehicle starts. If the engine does not start and the
key is held in START, cranking will be stopped
after 15 seconds to prevent cranking motor
damage. To prevent gear damage, this system also
prevents cranking if the engine is already running.
Engine cranking can be stopped by turning the
ignition switch to the ACC/ACCESSORY or LOCK/
OFF position.
Notice: Cranking the engine for long periods of
time, by returning the key to the START position
immediately after cranking has ended, can overheat
and damage the cranking motor, and drain the
battery. Wait at least 15 seconds between each try,
to let the cranking motor cool down. 2. If the engine does not start after 5‐10 seconds,
especially in very cold weather (below 0°F or
−18°C), it could be flooded with too much gasoline.
Try pushing the accelerator pedal all the way to the
floor and holding it there as you hold the key in
START for up to a maximum of 15 seconds. Wait at
least 15 seconds between each try, to allow the
cranking motor to cool down. When the engine
starts, let go of the key and accelerator. If the
vehicle starts briefly but then stops again, repeat
these steps. This clears the extra gasoline from the
engine. Do not race the engine immediately after
starting it. Operate the engine and transmission
gently until the oil warms up and lubricates all
moving parts.
Notice: The engine is designed to work with the
electronics in the vehicle. If you add electrical
parts or accessories, you could change the way
the engine operates. Before adding electrical
equipment, check with your dealer/retailer. If you
do not, the engine might not perform properly. Any
resulting damage would not be covered by the
vehicle warranty.
3-25

Adjustable Throttle and Brake Pedal
On vehicles with this feature, you can change the
position of the throttle and brake pedals.
No adjustment to the pedals can be made when the
vehicle is in R (Reverse) or while using the cruise
control.
The switch used to adjust
the pedals is located on
the instrument panel
below the climate control
system.
Press the arrow at the bottom of the switch to move the
pedals closer to your body. Press the arrow at the top of
the switch to move the pedals away from your body.
Before you start driving, fully press the brake pedal to
confirm the adjustment is right for you. While driving,
make only small adjustments. The vehicle may have a memory function which lets
pedal settings be saved and recalled. See
Memory
Features
on page 2‑6for more information.
Engine Coolant Heater
The engine coolant heater can provide easier starting
and better fuel economy during engine warm-up in cold
weather conditions at or below −18°C (0°F). Vehicles
with an engine heater should be plugged in at least four
hours before starting. An internal thermostat in the
plug-end of the cord may exist which will prevent engine
coolant heater operation at temperatures above
−18°C (0°F).
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord. The cord is secured to the Engine Compartment Fuse
Block with a clip. Carefully remove the wire tie
which secures the electrical cord. Do not cut the
electrical cord.
3. Plug the cord into a normal, grounded 110-volt AC outlet.
3-26

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 3‑35for 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 3‑35. If you are pulling a trailer,
see Towing a Trailer on page 5‑42.
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.
3-28

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).
3-35

Torque Lock
If you are parking on a hill and you do not shift the
transmission into P (Park) properly, the weight of the
vehicle can put too much force on the parking pawl in
the transmission. It might be difficult to pull the shift
lever out of P (Park). This is called torque lock. To
prevent torque lock, set the parking brake and then shift
into P (Park) properly before you leave the driver seat.
To find out how, seeShifting Into Park on page 3‑35.
When you are ready to drive, move the shift lever out of
P (Park) before releasing the parking brake.
If torque lock does occur, you might need to have
another vehicle push yours a little uphill to take some of
the pressure from the parking pawl in the transmission.
Then you should be able to pull the shift lever out of
P (Park).
Shifting Out of Park
This vehicle is equipped with an electronic shift lock
release system. The shift lock release is designed to:
.Prevent ignition key removal unless the shift lever
is in P (Park) with the shift lever button fully
released, and
.Prevent movement of the shift lever out of P (Park),
unless the ignition is in ON/RUN or ACC/
ACCESSORY and the regular brake pedal is
applied. The shift lock release is always functional except in the
case of an uncharged or low voltage (less than 9 volt)
battery.
If the vehicle has an uncharged battery or a battery
with low voltage, try charging or jump starting the
battery. See
Jump Starting
on page 6‑44for more
information.
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.
3-36

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.
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).(Continued)
WARNING: (Continued)
.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.
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.
3-37

Resetting the Power Foldaway Mirrors
Reset the power foldaway mirrors if:
.The mirrors are accidentally obstructed while
folding.
.They are accidentally manually folded/unfolded.
.The mirrors will not stay in the unfolded position.
.The mirrors vibrate at normal driving speeds.
Fold and unfold the mirrors one time using the mirror
controls to reset them to their normal position.
A popping noise may be heard during the resetting of
the power foldaway mirrors. This sound is normal after
a manual folding operation.
Automatic Dimming
The driver outside mirror adjusts for the glare of the
headlamps behind you. See Automatic Dimming
Rearview Mirror
on page 3‑39for more information.
Turn Signal Indicator
The vehicle may also have a turn signal indicator on the
mirror. An arrow on the mirror flashes in the direction of
the turn or lane change.
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). See DIC Vehicle Customization (With DIC
Buttons)
on page 4‑67for more information.
3-41

The system can be
disabled by pressing the
rear park aid disable
button located next to the
radio.
The indicator light will come on and PARK ASSIST OFF
displays on the Driver Information Center (DIC) to
indicate that URPA is off, see DIC Warnings and
Messages on page 4‑57.
Notice: If you use URPA while the tailgate is
lowered, it may not detect an object behind your
vehicle, and you might back into the object and
damage your vehicle. Always verify the tailgate is
closed when using URPA or turn off URPA when
driving with the tailgate lowered.
When the System Does Not Seem to
Work Properly
If the URPA system will not activate due to a temporary
condition, the messages PARK ASSIST OFF or PARK
ASST BLOCKED SEE OWNERS MANUAL will be
displayed on the DIC.
SERVICE PARK ASSIST : If this message occurs, take
the vehicle to your dealer/retailer to repair the system. PARK ASSIST OFF :
This message occurs if the driver
disables the system.
PARK ASST BLOCKED SEE OWNERS MANUAL :
This message can occur under the following conditions:
.The ultrasonic sensors are not clean. Keep the
vehicle's rear bumper free of mud, dirt, snow, ice
and slush. For cleaning instructions, see Washing
Your Vehicle on page 6‑108.
.The park assist sensors are covered by frost or
ice. Frost or ice can form around and behind the
sensors and may not always be seen; this can
occur after washing the vehicle in cold weather.
The message may not clear until the frost or ice
has melted.
.A trailer was attached to the vehicle, or a bicycle or
an object was hanging out of the tailgate during the
last drive cycle. Once the attached object is
removed and the tailgate is raised, URPA will
return to normal operation.
.A tow bar is attached to the vehicle.
.The vehicle's bumper is damaged. Take the vehicle
to your dealer/retailer to repair the system.
.Other conditions may affect system performance,
such as vibrations from a jackhammer or the
compression of air brakes on a very large truck.
3-44