lock GMC YUKON 2010 Repair Manual

B (ACC/ACCESSORY):This position lets things like
the radio and the windshield wipers operate while the
engine is off. Use this position if the vehicle must be
pushed or towed.
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
If the vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
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 are 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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Starting Procedure
1. With your foot off the accelerator pedal, turn theignition key to START. When the engine starts, let
go of the key. The idle speed will go down as the
engine gets warm. 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 for many seconds, 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, do the
same thing. 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. If you do
not, the engine might not perform properly.
Any resulting damage would not be covered
by the vehicle warranty.
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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.{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 in the area
where you will be parking the vehicle for the best advice
on this.
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Heavy Duty 6-Speed Automatic Transmission Shown(Light Duty Similar)
See “Range Selection Mode” later in this section.
P (Park): This position locks the rear wheels. It is the
best position to use when starting the engine because
the vehicle cannot move easily. When parked on a hill,
especially when the vehicle has a heavy load, you
might notice an increase in the effort to shift out of
P (Park). See Torque Lock (Automatic Transmission)
under Shifting Into Park
on page 3‑49for 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 3‑49. If you are pulling a trailer,
see Towing a Trailer on page 5‑49.
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Shifting into Neutral
To shift the transfer case to N (Neutral) do the following:1. Make sure the vehicle is parked so that it will not roll.
2. Set the parking brake and apply the regular brake pedal. See Parking Brake
on page 3‑48for more
information.
3. Start the vehicle or turn the ignition to ON/RUN.
4. Put the transmission in N (Neutral).
5. Shift the transfer case to Two-Wheel Drive High.
6. Turn the transfer case dial clockwise to N (Neutral) until it stops and hold it there until the N (Neutral)
light starts blinking. This will take at least
10 seconds. Then slowly release the dial to the
Four‐Wheel Drive Low position. The N (Neutral)
light will come on when the transfer case shift to
N (Neutral) is complete.
7. If the engine is running, verify that the transfer case is in N (Neutral) by shifting the transmission
to R (Reverse) for one second, then shift the
transmission to D (Drive) for one second. 8. Turn the ignition to ACC/ACCESSORY, which will
turn the engine off.
9. Place the transmission shift lever in P (Park).
10. Release the parking brake prior to moving the vehicle.
11. Turn the ignition to LOCK/OFF.
Shifting Out of Neutral
To shift out of N Neutral do the following: 1. Set the parking brake and apply the regular brake pedal.
2. Turn the ignition to ON/RUN with the engine off, and shift the transmission to N (Neutral).
3. Turn the transfer case dial to the desired transfer case shift position (Two-Wheel Drive High,
Four-Wheel Drive High, AUTO).
After the transfer case has shifted out of
N (Neutral), the N (Neutral) light will go out.
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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 5‑49.
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 have a four-wheel drive transfer case with
a N (Neutral) position, and the transfer case is in(Continued)
WARNING: (Continued)
N (Neutral), the vehicle will be free to roll, even
if the shift lever is in P (Park). So, be sure the
transfer case is in a drive gear—not in
N (Neutral). If you are pulling a trailer, see Towing
a Trailer
on page 5‑49. Always set the parking
brake.
1. Hold the brake pedal down, then set the parking brake.
See Parking Brake
on page 3‑48for more
information.
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. Be sure the transfer case is in a drive gear —not
in N (Neutral).
4. Turn the ignition key to LOCK/OFF.
5. 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).
3-49

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.
If you have four-wheel drive and the transfer case
is in N (Neutral), the vehicle will be free to roll,
even if the shift lever is in P (Park). So be sure
the transfer case is in a drive gear—not in
N (Neutral).
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 unless you
have to.
If you have to leave the vehicle with the engine running,
be sure your vehicle is in P (Park) and the parking
brake is firmly set before you leave it. After you move the shift lever 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).
Torque Lock
If you are parking on a hill and you do not shift your
transmission into P (Park) properly, the weight of the
vehicle may put too much force on the parking pawl
in the transmission. You may find it 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, see
Shifting Into Park
on
page 3‑49.
When you are ready to drive, move the shift lever out of
P (Park) before you release the parking brake.
If torque lock does occur, you may 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 will be able to pull the shift lever out of
P (Park).
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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 6‑46for 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.
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.
3-51

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.(Continued)
WARNING: (Continued)
.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.
3-52

WARNING: (Continued)
If you do not use proper care before and while
backing; vehicle damage, injury, or death could
occur. Even with URPA, always check behind the
vehicle before backing up. While backing, be sure
to look for objects and check the vehicle's mirrors.
How the System Works
URPA comes on automatically when the shift lever
is moved into R (Reverse). A single tone sounds to
indicate the system is working.
URPA operates only at speeds less than
5 mph (8 km/h).
An obstacle is indicated by audible beeps. The interval
between the beeps becomes shorter as the vehicle gets
closer to the obstacle. When the distance is less than
30 cm (12 in) the beeps are continuous.
To be detected, objects must be at least 25.4 cm (10 in)
off the ground and below liftgate level. Objects must
also be within 2.5 m (8 ft) from the rear bumper. This
distance may be less during warmer or humid weather.
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 4‑61.
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 to repair the system.
PARK ASSIST OFF: This message occurs if the driver
disables the system.
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