2008 GMC SIERRA Owner's Manual

Outside Power Foldaway Mirrors
If your vehicle is equipped
with outside power
foldaway mirrors, the
controls are located on the
driver’s door armrest.
Press (A) to select the driver’s side mirror. Then
press the arrows located on the four-way control
pad to adjust the mirror. Press (A) again to deselect
the mirror.
Press (B) to select the passenger’s side mirror.
Then press the arrows located on the four-way
control pad to adjust the mirror. Press (B) again to
deselect the mirror.
Press (C) to fold the mirrors out to the driving
position.
Press (D) to fold the mirrors in to the folded
position.If the mirrors are accidentally folded/unfolded manually,
they may shake or utter at normal driving speeds
and may not stay in the unfolded position. If this
happens, you will need to reset the mirrors. See
“Resetting the Power Foldaway Mirrors” next.
Resetting the Power Foldaway Mirrors
You will need to reset the power foldaway mirrors if the
following occurs:
The mirrors are accidentally obstructed while
folding.
They are accidentally manually folded/unfolded.
The mirrors will not stay in the unfolded position.
The mirrors shake and utter at normal driving
speeds.
To reset the power foldaway mirrors, fold and unfold
them one time using the mirror controls. This will reset
them to their normal position.
This mirror has the following features.
Automatic Dimming
The driver’s outside mirror will adjust for the glare of the
headlamps behind you. SeeAutomatic Dimming
Rearview Mirror with OnStar
®, Compass and
Temperature Display on page 2-55.
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Park Tilt Mirrors
If your vehicle has the memory package, the outside
mirrors are able to perform the park tilt function. This
feature may be useful in allowing the driver to view the
curb when parallel parking. This feature will cause the
passenger’s and/or driver’s mirror to tilt to a preselected
position when the vehicle is in REVERSE (R).
The passenger’s and/or driver’s mirror will return to its
original position when the vehicle is shifted out of
REVERSE (R), or the ignition is turned off or to
OFF/LOCK.
This feature can be turned on or off through the Driver
Information Center (DIC). SeeDIC Vehicle
Customization (With DIC Buttons) on page 3-72.
Heated Mirrors
The button to turn the heated mirrors on or off is located
on the climate control panel. Press this button to
warm the driver’s and passenger’s outside rearview
mirrors to help clear them of ice, snow, and
condensation.
See “Rear Window Defogger” underDual Automatic
Climate Control System on page 3-28for more
information.
Convex Mirror
{CAUTION:
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 your right. Check your
inside mirror or glance over your shoulder
before changing lanes.
The passenger’s side mirror may have convex glass. A
convex mirror’s surface is curved so more can be
seen from the driver’s seat.
Your vehicle may also have a turn signal indicator on
the mirror. An arrow on the mirror will ash in the
direction of the turn or lane change.
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Object Detection Systems
Ultrasonic Rear Parking
Assist (URPA)
If your vehicle has the Ultrasonic Rear Parking Assist
(URPA) system, it helps you park easier and avoid other
vehicles while in REVERSE (R). It operates at speeds
less than 5 mph (8 km/h). It can determine how close
objects are to the rear bumper, up to 8 feet (2.5 m)
behind your vehicle. The distance sensors are located
on the rear bumper.
{CAUTION:
The Ultrasonic Rear Parking Assist (URPA)
system does not replace driver vision.
It cannot detect:
objects that are below the bumper,
underneath the vehicle, or if they are too
close or far from the vehicle
children, pedestrians, bicyclists, or pets.
CAUTION: (Continued)
CAUTION: (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 your vehicle before backing up. While
backing, be sure to look for objects and check
your vehicle’s mirrors.
On some vehicles this
display is located near
the passenger side
rear window and can be
seen by looking over
your right shoulder.
If your vehicle has the display, there are three
color-coded lights to provide distance and system
information.
If your vehicle does not have the display and it has
URPA, you will hear the beeps as described in the
following information.
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How the System Works
URPA comes on automatically when the shift lever is
moved into REVERSE (R). The rear display will
then briey illuminate to let you know the system is
working.
URPA operates only at speeds less than 5 mph
(8 km/h). If you are above this speed, the red light on
the rear display will ash.
To be detected, objects must be at least 10 inches
(25.4 cm) off the ground and below tailgate level.
Objects must also be within 8 feet (2.5 m) from your
rear bumper. This distance may be less during warmer
or humid weather.
A single beep will sound the rst time an object is
detected between 20 inches (0.5 m) and 8 feet (2.5 m)
away. Beeping will occur for three seconds when
you are closer than 1 foot (0.3 m) from the object.The following describes what will occur with the URPA
display as you get closer to a detected object:
Description English Metric
amber light 8 ft 2.5 m
amber/amber lights 40 in 1.0 m
amber/amber/red lights 23 in 0.6 m
amber/amber/red lights
ashing and beep for
three seconds1 ft 0.3 m
The system can be
disabled by pressing the
rear park aid disable button
located next to the radio.
The indicator light will
come on to indicate that
URPA is off.
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.
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When the System Does Not Seem to
Work Properly
The driver disables the system.
The parking brake pedal is depressed.
The ultrasonic sensors are not clean. Keep your
vehicle’s rear bumper free of mud, dirt, snow,
ice and slush. For cleaning instructions, see
Washing Your Vehicle on page 5-116.
A trailer was attached to your vehicle, or a bicycle
or an object was hanging out of your tailgate
during your last drive cycle, the red light may
illuminate in the rear display. Once the attached
object is removed, URPA will return to normal
operation.
A tow bar is attached to your 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.
If the system is still disabled, after driving forward at
least 15 mph (25 km/h), take your vehicle to your
dealer/retailer.
OnStar®System
OnStar uses several innovative technologies and live
advisors to provide you with a wide range of safety,
security, information, and convenience services. If your
airbags deploy, the system is designed to make an
automatic call to OnStar Emergency advisors who can
request emergency services be sent to your location.
If you lock your keys in the vehicle, call OnStar at
1-888-4-ONSTAR and they can send a signal to unlock
your doors. If you need roadside assistance, press
the OnStar button and they can contact Roadside
Service for you.
OnStar service is provided to you subject to the OnStar
Terms and Conditions. You may cancel your OnStar
service at any time by contacting OnStar. A complete
OnStar Owner’s Guide and the OnStar Terms and
Conditions are included in the vehicle’s OnStar
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Subscriber glove box literature. For more information,
visit onstar.com or onstar.ca, contact OnStar at
1-888-4-ONSTAR (1-888-466-7827) or TTY
1-877-248-2080, or press the OnStar button to speak
with an OnStar advisor 24 hours a day, 7 days a week.
Not all OnStar features are available on all vehicles.
To check if your vehicle is equipped to provide the
services described below, or for a full description of
OnStar services and system limitations, see the OnStar
Owner’s Guide in your glove box or visit onstar.com.
OnStar Services
For new vehicles with OnStar, the Safe & Sound Plan,
or the Directions & Connections Plan is included for
one year from the date of purchase. You can extend this
plan beyond the rst year, or upgrade to the Directions
& Connections Plan. For more information, press
the OnStar button to speak with an advisor. Some
OnStar services (such as Remote Door Unlock or Stolen
Vehicle Location Assistance) may not be available
until you register with OnStar.
Available Services with Safe & Sound Plan

Automatic Notication of Airbag Deployment
Advanced Automatic Crash Notication (AACN)
(If equipped)
Link to Emergency Services
Roadside Assistance
Stolen Vehicle Location Assistance
AccidentAssist
Remote Door Unlock/Vehicle Alert
OnStar Vehicle Diagnostics
GM Goodwrench®On Demand Diagnostics
OnStar Hands-Free Calling with 30 complimentary
minutes
OnStar Virtual Advisor (U.S. Only)
Available Services included with Directions
& Connections Plan

All Safe and Sound Plan Services
Driving Directions - Advisor delivered or OnStar
Turn-by-Turn Navigation (If equipped)
RideAssist
Information and Convenience Services
OnStar Hands-Free Calling
OnStar Hands-Free Calling allows eligible OnStar
subscribers to make and receive calls using voice
commands. Hands-Free Calling is fully integrated into
the vehicle, and can be used with OnStar Pre-Paid
Minute Packages. Hands-Free Calling may also
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be linked to a Verizon Wireless service plan in the U.S.
or a Bell Mobility service plan in Canada, depending
on eligibility. To nd out more, refer to the OnStar
Owner’s Guide in the vehicle’s glove box, visit
www.onstar.com or www.onstar.ca, or speak with an
OnStar advisor by pressing the OnStar button or calling
1-888-4-ONSTAR (1-888-466-7827).
OnStar Virtual Advisor
OnStar Virtual Advisor is a feature of OnStar
Hands-Free Calling that uses your minutes to access
location-based weather, local traffic reports, and
stock quotes. By pressing the phone button and giving
a few simple voice commands, you can browse
through the various topics. See the OnStar Owner’s
Guide for more information (Only available in the
continental U.S.).
OnStar Steering Wheel Controls
Your vehicle may have a Talk/Mute button that can be
used to interact with OnStar Hands-Free Calling.
SeeAudio Steering Wheel Controls on page 3-124for
more information.
On some vehicles, you may have to hold the button for
a few seconds and give the command “ONSTAR” to
activate the OnStar Hands-Free Calling.On some vehicles, the mute button can be used to dial
numbers into voicemail systems, or to dial phone
extensions. See the OnStar Owner’s Guide for more
information.
How OnStar Service Works
Your vehicle’s OnStar system has the capability of
recording and transmitting vehicle information. This
information is automatically sent to an OnStar Call
Center at the time of an OnStar button press,
Emergency button press or if your airbags or AACN
system deploys. The vehicle information usually includes
your GPS location and, in the event of a crash,
additional information regarding the accident that your
vehicle has been involved in (e.g. the direction from
which your vehicle was hit). When you use the Virtual
Advisor feature of OnStar Hands-Free Calling, your
vehicle also sends OnStar your GPS location so that we
can provide you with location-based services.
OnStar service cannot work unless your vehicle is in a
place where OnStar has an agreement with a wireless
service provider for service in that area. OnStar
service also cannot work unless you are in a place
where the wireless service provider OnStar has hired for
that area has coverage, network capacity and reception
when the service is needed, and technology that is
compatible with the OnStar service. Not all services are
available everywhere, particularly in remote or
enclosed areas, or at all times.
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Location information about your vehicle is only available
if the GPS satellite signals are unobstructed and
available.
Your vehicle must have a working electrical system
(including adequate battery power) for the OnStar
equipment to operate. There are other problems OnStar
cannot control that may prevent OnStar from providing
OnStar service to you at any particular time or place.
Some examples are damage to important parts of your
vehicle in an accident, hills, tall buildings, tunnels,
weather or wireless phone network congestion.
Your Responsibility
Increase the radio volume if you cannot hear the OnStar
advisor. If the light next to the OnStar buttons is red,
this means that your system is not functioning properly
and should be checked by your dealer/retailer. If the
light appears clear (no light is appearing), your OnStar
subscription has expired. You can always press the
OnStar button to conrm that your OnStar equipment
is active.
Universal Home Remote
System
Universal Home Remote System
The Universal Home Remote System provides a way to
replace up to three hand-held Radio-Frequency (RF)
transmitters used to activate devices such as garage
door openers, security systems, and home lighting.
This device complies with Part 15 of the FCC Rules.
Operation is subject to the following two conditions:
1. This device may not cause harmful interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation.
This device complies with RSS-210 of Industry Canada.
Operation is subject to the following two conditions:
1. This device may not cause interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
Changes or modications to this system by other than
an authorized service facility could void authorization to
use this equipment.
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