light GMC YUKON 2010 Service Manual

Shifting Out of Four-Wheel Drive Low
To shift from Four-Wheel Drive Low to Four-Wheel Drive
High, AUTO, or Two-Wheel Drive High, the vehicle must
be stopped or moving less than 3 mph (5 km/h) with the
transmission in N (Neutral) and the ignition in ON/RUN.
The preferred method for shifting out of Four-Wheel
Drive Low is to have your vehicle moving 1 to 2 mph
(1.6 to 3.2 km/h). Turn the knob to the Four-Wheel
Drive High, AUTO, or Two-Wheel Drive High position.
You must wait for the Four-Wheel Drive High, AUTO,
or Two-Wheel Drive High indicator light to stop flashing
and remain on before shifting the transmission
into gear.
Notice:Shifting the transmission into gear before
the Four-Wheel Drive Low indicator light has
stopped flashing could damage the transfer case.
To help avoid damaging the vehicle, always wait for
the Four-Wheel Drive Low indicator light to stop
flashing before shifting the transmission into gear. The vehicle may have significant engagement noise
and bump when shifting between Four-Wheel Drive Low
and Four-Wheel Drive High ranges or from N (Neutral)
while the engine is running.
If the knob is turned to the Four-Wheel Drive High,
AUTO, or Two-Wheel Drive High switch position when
the vehicle is in gear and/or moving, the Four-Wheel
Drive High, AUTO or Two-Wheel Drive High indicator
light will flash for 30 seconds but will not complete the
shift unless the vehicle is moving less than 3 mph
(5 km/h) and the transmission is in N (Neutral).
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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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4. Release the parking brake prior to moving thevehicle.
Notice: Shifting the transmission into gear before
the Four-Wheel Drive Low indicator light has
stopped flashing could damage the transfer case.
To help avoid damaging the vehicle, always wait for
the Four-Wheel Drive Low indicator light to stop
flashing before shifting the transmission into gear.
5. Start the engine and shift the transmission to the desired position.
Excessively shifting the transfer case into or out of the
different modes may cause the transfer case to enter
the shift protection mode. This will protect the transfer
case from possible damage and will only allow the
transfer case to respond to one shift per 10 seconds.
The transfer case may stay in this mode for up to
three minutes.Four-Wheel Drive (Single Speed
Automatic Transfer Case)
If the vehicle has four-wheel drive, you can send the
engine's driving power to all four wheels for extra
traction. Read the following before using four-wheel
drive.
Notice: Driving on clean, dry pavement in
Four-Wheel Drive High for an extended period of
time may cause premature wear on the vehicle's
powertrain. Do not drive on clean, dry pavement in
Four-Wheel Drive High for extended periods of time.
While driving on clean dry pavement and during tight
turns, you may experience a vibration in the steering
system.
Front Axle
The front axle engages and disengages automatically
when you shift the transfer case. Some delay for the
axle to engage or disengage is normal.
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Automatic Transfer Case
The transfer case knob is
located to the left of the
instrument panel cluster.
Use this dial to shift into and out of four-wheel drive.
The vehicle has Four-Wheel-Drive with StabiliTrak
®.
For information on StabiliTrak®, see StabiliTrak®Systemon page 5‑6.
You can choose among three driving settings:
Indicator lights in the switch show you which setting you
are in. The indicator lights will come on briefly when you
turn on the ignition and the last chosen setting will stay
on. If the lights do not come on, you should take the
vehicle to your dealer for service. An indicator light will flash while shifting. It will stay on when the shift is
completed. If for some reason the transfer case cannot
make a requested shift, it will return to the last chosen
setting.
2
m(Two-Wheel Drive High):
This setting is used for
driving in most street and highway situations. The front
axle is not engaged in two-wheel drive. This setting also
provides the best fuel economy.
AUTO (Automatic Four-Wheel Drive): This setting is
ideal for use when road surface traction conditions are
variable. When driving the vehicle in AUTO, the front
axle is engaged, but the vehicle's power is primarily
sent to the rear wheels. When the vehicle's software
determines a need for more traction, the system will
transfer more power to the front wheels. Driving in
this mode results in slightly lower fuel economy than
Two-Wheel Drive High.
4
m(Four-Wheel Drive High): Use the four-wheel
high position when you need extra traction, such as
on snowy or icy roads or in most off-road situations.
This setting also engages the front axle to help drive
the vehicle. This is the best setting to use when
plowing snow.
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Service Four Wheel Drive
If the SERVICE 4 WHEEL DRIVE message stays on,
you should take the vehicle to your dealer for service.
See“SERVICE 4 WHEEL DRIVE message” underDIC
Warnings and Messages on page 4‑61.
Shifting Into Four-Wheel Drive High or
AUTO (Automatic Four-Wheel Drive)
Turn the knob to the Four-Wheel High or AUTO
position. This can be done at any speed. The indicator
light will flash while shifting. It will remain on when the
shift is completed.
Shifting Into Two-Wheel Drive High
Turn the knob to the Two-Wheel High position. This can
be done at any speed. The indicator light will flash while
shifting. It will remain on when the shift is completed.
Excessively shifting the transfer case into or out of the
different modes may cause the transfer case to enter
the shift protection mode. This will protect the transfer
case from possible damage and will only allow the
transfer case to respond to one shift per 10 seconds.
The transfer case may stay in this mode for up to
three minutes.
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 4‑36.
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.
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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).
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Mirrors
Manual Rearview Mirror
Hold the inside rearview mirror in the center to move it
for a clearer view behind your vehicle. Adjust the mirror
to avoid glare from the headlamps behind you. Push the
tab forward for daytime use and pull it for nighttime use.
Automatic Dimming Rearview Mirror
The vehicle may have an automatic dimming rearview
mirror.
Vehicles with OnStar
®have three additional control
buttons for the OnStar®system. See your dealer for
more information about OnStar®and how to subscribe
to it. See the OnStar®owner's guide for more
information about the services OnStar®provides.
O(On/Off): Press to turn the dimming feature on or off.
The vehicle may also have a Rear Vision Camera
(RVC). See Rear Vision Camera (RVC)
on page 3‑64for more information.
If the vehicle has RVC, the
O(On/Off) button for
turning the automatic dimming feature on or off will
not be available.
Automatic Dimming Mirror Operation
Automatic dimming reduces the glare from the
headlamps of the vehicle behind you. The dimming
feature comes on and the indicator light illuminates
each time the ignition is turned to start.
Cleaning the Mirror
Do not spray glass cleaner directly on the mirror.
Use a soft towel dampened with water.
Outside Manual Mirrors
Adjust the outside mirror for a clearer view.
Manually fold the mirrors inward to prevent damage
when going through an automatic car wash. To fold,
push the mirror toward the vehicle. Push the mirror
outward, to return to its original position.
Using hood-mounted air deflectors and add-on convex
mirror attachments could decrease mirror performance.
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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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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, seeWashing
Your Vehicle on page 6‑112.
.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 liftgate during
the last drive cycle. Once the attached object is
removed, 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 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.
If the system is still disabled, after driving forward at
least 40 km/h (25 mph), take the vehicle to your dealer.
Side Blind Zone Alert (SBZA)
The vehicle may have a Side Blind Zone Alert (SBZA)
system. Read this entire section before using the
system.
{WARNING:
SBZA is only a lane changing aid and does not
replace driver vision. SBZA does not detect:
.Vehicles outside the side blind zones which
may be rapidly approaching.
.Pedestrians, bicyclists, or animals.
Failure to use proper care when changing lanes
may result in damage to the vehicle, injury,
or death. Always check the outside and rearview
mirrors, glance over your shoulder, and use the
turn signal before changing lanes.
When the system detects a vehicle in the side blind
zone, amber SBZA displays light up in the side mirrors.
This indicates that it may be unsafe to change lanes.
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Before making a lane change, always check the SBZA
display, check the outside and rearview mirrors, look
over your shoulder for vehicles and hazards, and use
the turn signal.
SBZA Detection Zones
The SBZA sensor covers a zone of approximately one
lane over from both sides of the vehicle, 3.5 m (11 ft).
This zone starts at each side mirror and goes back
approximately 5.0 m (16 ft). The height of the zone is
approximately between 0.5 m (1.5 ft) and 2.0 m (6 ft) off
the ground.Use caution while changing lanes when towing a trailer,
as the SBZA detection zones do not change when a
trailer is towed.
How the System Works
Left Side Mirror DisplayRight Side Mirror Display
When the vehicle is started, both outside mirror displays
will briefly come on to indicate that the system is
operating. When the vehicle is moving forward, the left
or right side mirror SBZA display will light up if a vehicle
is detected in that blind zone. If the turn signal is
activated and a vehicle is also detected on the same
side, the SBZA display will flash to give you extra
warning not to change lanes.
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