2010 GMC YUKON XL trailer

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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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 3‑52.
{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.
(Continued)
WARNING: (Continued)
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).
{WARNING:
If the vehicle has a four-wheel drive transfer case
with a N (Neutral) position, and the transfer case
is in N (Neutral), the vehicle may roll, even if the
automatic transmission shift lever is in P (Park).
So, be sure the transfer case is in a drive
gear—not in N (Neutral). Always set the
parking brake.
Follow the proper steps to be sure the vehicle will not
move. See Shifting Into Park on page 3‑49.
If pulling a trailer, see Towing a Trailer on page 5‑49.
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Outside Towing Mirrors
If the vehicle has towing mirrors, they can be adjusted
for a clearer view of the objects behind you. Manually
pull out the mirror head to extend it for better visibility
when towing a trailer.
Manually fold the mirrors forward or rearward. The lower
portion of the mirror is convex. A convex mirror's
surface is curved to see more from the driver seat.
The convex mirror can be adjusted manually to the
driver preferred position for better vision.
The mirror may have a turn signal arrow that flashes in
the direction of the turn or lane change.
Outside Power Mirrors
Vehicles with outside
power mirrors have the
controls on the driver door
armrest.
To adjust each mirror: 1. Press (A) or (B) to select the driver or passenger side mirror.
2. Press one of the four arrows located on the control pad to move the mirror to the desired direction.
3. Adjust each outside mirror so that a little of the vehicle and the area behind it can be seen.
4. Press either (A) or (B) again to deselect the mirror.
The mirrors may also include a memory function that
works with the memory seats. See Memory Seat,
Mirrors, and Pedals
on page 2‑10for more information.
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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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SBZA displays do not come on while the vehicle is
approaching or passing other vehicles. At speeds
greater then 32 km/h (20 mph), SBZA displays may
come on when a vehicle you have passed remains in
or drops back into the detection zone.
SBZA can be disabled through the Driver Information
Center (DIC). SeeDriver Information Center (DIC)
on
page 4‑47for more information. If the SBZA is disabled
by the driver, the SBZA mirror displays will not light up
during normal driving.
When the System Does Not Seem To Work
Properly
Occasional missed alerts can occur under normal
circumstances and will increase in wet conditions.
The system does not need to be serviced due to an
occasional missed alert. The number of missed alerts
will increase with increased rainfall or road spray.
If the SBZA displays do not light up when the system is
on and vehicles are in the blind zone, the system may
need service. Take the vehicle to your dealer. SBZA is designed to ignore stationary objects; however,
the system may occasionally light up due to guard rails,
signs, trees, shrubs, and other stationary objects. This
is normal system operation, the vehicle does not need
service.
SBZA does not operate when the left or right corners of
the rear bumper are covered with mud, dirt, snow, ice,
slush, or in heavy rainstorms. For cleaning instructions,
see
Washing Your Vehicle
on page 6‑112. If the DIC still
displays the SIDE BLIND ZONE SYS. UNAVAILABLE
message after cleaning the bumper, see your dealer.
The SBZA displays may remain on if a trailer is
attached to the vehicle, or a bicycle or object is
extending out to either side of the vehicle.
When SBZA is disabled for any reason other than the
driver turning it off, the driver will not be able to turn
SBZA back on using the DIC. The SIDE BLIND ZONE
ALERT ON option will not be selectable if the conditions
for normal system operation are not met. Until normal
operating conditions for SBZA are met, you should not
rely upon SBZA while driving.
3-62

Entry Lighting
The vehicle has an illuminated entry feature.
When the doors are opened, the dome lamps will
come on if the dome override button is in the extended
position. If the dome override button is pressed in, the
lamps will not come on.
Exit Lighting
The interior lamps come on when the key is removed
from the ignition. They turn off automatically in
20 seconds. The lights do not come on if the dome
override button is pressed in.
Reading Lamps
For vehicles with reading lamps they are located on the
overhead console.
To turn on the reading lamps, press the button located
next to each lamp. To turn them off, press the button
again.
The vehicle may also have reading lamps in other
locations. To turn the lamps on or off, press the button
located next to the lamp.
The lamps are fixed and cannot be adjusted.
Electric Power Management
The vehicle has Electric Power Management (EPM) that
estimates the battery's temperature and state of charge.
It then adjusts the voltage for best performance and
extended life of the battery.
When the battery's state of charge is low, the voltage
is raised slightly to quickly bring the charge back up.
When the state of charge is high, the voltage is lowered
slightly to prevent overcharging. If the vehicle has a
voltmeter gauge or a voltage display on the Driver
Information Center (DIC), you may see the voltage
move up or down. This is normal. If there is a problem,
an alert will be displayed.
The battery can be discharged at idle if the electrical
loads are very high. This is true for all vehicles. This is
because the generator (alternator) may not be spinning
fast enough at idle to produce all the power that is
needed for very high electrical loads.
A high electrical load occurs when several of the
following are on, such as: headlamps, high beams, fog
lamps, rear window defogger, climate control fan at high
speed, heated seats, engine cooling fans, trailer loads,
and loads plugged into accessory power outlets.
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If the check engine light comes on and stays on, while
the engine is running, this indicates that there is an
OBD II problem and service is required.
Malfunctions often are indicated by the system before
any problem is apparent. Being aware of the light
can prevent more serious damage to the vehicle.
This system assists the service technician in correctly
diagnosing any malfunction.
Notice:If the vehicle is continually driven with this
light on, after a while, the emission controls might
not work as well, the vehicle's fuel economy might
not be as good, and the engine might not run as
smoothly. This could lead to costly repairs that
might not be covered by the vehicle warranty.
Notice: Modifications made to the engine,
transmission, exhaust, intake, or fuel system
of the vehicle or the replacement of the original
tires with other than those of the same Tire
Performance Criteria (TPC) can affect the vehicle's
emission controls and can cause this light to come
on. Modifications to these systems could lead to
costly repairs not covered by the vehicle warranty.
This could also result in a failure to pass a required
Emission Inspection/Maintenance test. See
Accessories and Modifications on page 6‑4. This light comes on during a malfunction in one of
two ways:
Light Flashing:
A misfire condition has been detected.
A misfire increases vehicle emissions and could
damage the emission control system on the vehicle.
Diagnosis and service might be required.
To prevent more serious damage to the vehicle:
.Reduce vehicle speed.
.Avoid hard accelerations.
.Avoid steep uphill grades.
.If towing a trailer, reduce the amount of cargo
being hauled as soon as it is possible.
If the light continues to flash, when it is safe to do so,
stop the vehicle. Find a safe place to park the vehicle.
Turn the vehicle off, wait at least 10 seconds, and
restart the engine. If the light is still flashing, follow the
previous steps and see your dealer for service as soon
as possible.
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