Page 66 of 556

Black plate (22,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
2-22 Keys, Doors, and Windows
Roof
Sunroof (Extended Cab)
On vehicles with a sunroof, the
sunroof only operates when the
ignition is in the ACC/ACCESSORY
or ON/RUN or the Retained
Accessory Power (RAP) is active.
SeeRetained Accessory Power
(RAP) on page 9‑29 for more
information. Vent:
From the closed position,
press and hold the rear of the switch
to vent the sunroof. To close the
sunroof, press and hold the front of
the switch.
Open: From the vent position,
the sunroof can be fully opened
either manually or by using the
express-open feature. To open
manually, press the rear of the
switch to the first detent and hold
until the sunroof has reached the
desired position. To open using
express-open, press the rear of the
switch to the second detent and
release. The sunroof will move to
the full open position. To stop the
sunroof partway, press the switch a
second time.
Close: From the vent, or open
position, press and hold the front of
the switch to close the sunroof.
The sunroof also has a roller
sunshade that can be used to
block the rays of the sun. The
roller sunshade can be manually
operated with the sunroof in an open or closed position. To open the
sunshade, press and unlatch it, and
roll it back. To close, pull it forward
and latch it into the closed position.
When the sunroof is opened, an air
deflector will automatically raise.
The air deflector will retract when
the sunroof is closed.Dirt and debris may collect on the
sunroof seal or in the track. This
could cause an issue with sunroof
operation or noise. It could also
plug the water drainage system.
Periodically open the sunroof and
remove any obstacles or loose
debris. Wipe the sunroof seal and
roof sealing area using a clean
cloth, mild soap, and water. Do not
remove grease from the sunroof.
Page 67 of 556

Black plate (23,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Keys, Doors, and Windows 2-23
Sunroof (Crew Cab)
A. Open or Close
B. Vent
On vehicles with a sunroof, the
sunroof only operates when the
ignition is in the ACC/ACCESSORY
or ON/RUN or the Retained
Accessory Power (RAP) is active.
SeeRetained Accessory Power
(RAP) on page 9‑29 for more
information.
Vent: From the closed position,
press the rear of the passenger side
switch (B) to vent the sunroof. Manual-Open/Manual-Close:
To
open the sunroof, press and hold
the rear of the driver side switch (A)
until the sunroof reaches the
desired position. Press and hold the
front of the driver side switch to
close it.
Express-Open/Express-Close:
To express-open the sunroof, fully
press and release the rear of the
driver side switch (A) until the
sunroof reaches the desired
position. To express-close the
sunroof, fully press and release
the front of the driver side switch.
Press the switch again to stop it.
When the sunroof is opened, an air
deflector will automatically raise.
The air deflector will retract when
the sunroof is closed.
The sunroof also has a sunshade
which can be pulled forward to block
sun rays. The sunshade must be
opened and closed manually. If an object is in the path of the
sunroof while it is closing, the
anti-pinch feature will detect the
object and stop the sunroof.Dirt and debris may collect on the
sunroof seal or in the track. This
could cause an issue with sunroof
operation or noise. It could also plug
the water drainage system.
Periodically open the sunroof and
remove any obstacles or loose
debris. Wipe the sunroof seal and
roof sealing area using a clean
cloth, mild soap, and water. Do not
remove grease from the sunroof.
Page 225 of 556

Black plate (15,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Infotainment System 7-15
Fixed Mast Antenna
The fixed mast antenna can
withstand most car washes without
being damaged as long as it is
securely attached to the base.
If the mast becomes slightly bent,
straighten it out by hand. If the mast
is badly bent, replace it.
Occasionally check to make sure
the antenna is tightened to its base.
If tightening is required, tighten
by hand until fully seated plus
one quarter turn.
Satellite Radio Antenna
The XM Satellite Radio antenna is
located on the roof of the vehicle.
Keep the antenna clear of
obstructions for clear radio
reception.
If the vehicle has a sunroof, the
performance of the XM system
(if equipped) may be affected if the
sunroof is open.
Audio Players
CD Player
Care of the CD Player
Do not add any label to a CD.
It could get caught in the CD. If a
CD is recorded on a personal
computer and a description label is
needed, try labeling the top of the
recorded CD with a marking pen.
The use of CD lens cleaners is
not advised, due to the risk of
contaminating the lens of the CD
optics with lubricants internal to the
CD player mechanism.
Notice:If a label is added to a
CD, more than one CD is inserted
into the slot at a time, or an
attempt is made to play scratched
or damaged CDs, the CD player
could be damaged. While using
the CD player, use only CDs in
good condition without any label,
load one CD at a time, and keep the CD player and the loading slot
free of foreign materials, liquids,
and debris.
If an error displays, see
“CD Player
Messages” later in this section.Care of CDs
If playing a CD-R, the sound quality
can be reduced due to CD-R or
CD-RW quality, the method of
recording, the quality of the music
that has been recorded, and the
way the CD-R or CD-RW has been
handled. Handle them carefully.
Store CD-Rs or CD-RWs in their
original cases or other protective
cases and away from direct sunlight
and dust. The CD player scans the
bottom surface of the disc. If the
surface of a CD is damaged, such
as cracked, broken, or scratched,
the CD does not play properly or not
at all. Do not touch the bottom side
of a CD while handling it; this could
damage the surface. Pick up CDs
by grasping the outer edges or the
edge of the hole and the outer edge.
Page 494 of 556

Black plate (4,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
11-4 Service and Maintenance
.Visually inspect steering,
suspension, and chassis
components for damaged, loose,
or missing parts or signs of
wear. SeeExterior Care on
page 10‑98.
.Check restraint system
components. See Safety System
Check on page 3‑20.
.Visually inspect fuel system for
damage or leaks.
.Visually inspect exhaust system
and nearby heat shields for
loose or damaged parts.
.Lubricate body components. See
Exterior Care on page 10‑98.
.Check starter switch. See Starter
Switch Check on page 10‑35.
.Check automatic transmission
shift lock control function. See
Automatic Transmission Shift
Lock Control Function Check on
page 10‑35.
.Check ignition transmission lock.
See Ignition Transmission Lock
Check on page 10‑35.
.Check parking brake and
automatic transmission park
mechanism. See Park Brake and
P (Park) Mechanism Check on
page 10‑36.
.Check accelerator pedal for
damage, high effort, or binding.
Replace if needed.
.Visually inspect gas strut for
signs of wear, cracks, or other
damage. Check the hold open
ability of the strut. See your
dealer if service is required.
.Inspect sunroof track and seal,
if equipped. See Sunroof (Crew
Cab) on page 2‑23 orSunroof
(Extended Cab) on page 2‑22.
.Check hybrid low pressure
coolant level, if equipped.