GMC SIERRA 1500 2012 Repair Manual

Black plate (17,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Keys, Doors, and Windows 2-17
Manual Folding
If equipped with manual folding
mirrors, push the mirror toward the
vehicle. Push the mirror outward, to
return to its original position.
Manually fold the mirrors inward to
prevent damage when going
through an automatic car wash.
Automatic Dimming
If equipped with an automatic
dimming mirror, the driver outside
mirror automatically dimes for the
glare of the headlamps from behind.
This feature is controlled by the on
and off setting on the inside
rearview mirror.
SeeAutomatic Dimming Rearview
Mirror on page 2‑18.
Turn Signal Indicator
The vehicle may also have a turn
signal indicator on the mirror. An
arrow on the mirror flashes in the
direction of the turn or lane change.
Heated Mirrors
For vehicles with heated mirrors:
1(Rear Window Defogger):
Press to heat the mirrors. If the
vehicle has a towing mirror, only the
upper glass of the mirror is heated.
The lower convex part of the towing
mirror is not heated.
Depending on the vehicle's features,
see “Rear Window Defogger” under
Climate Control Systems (with Air
Conditioning) on page 8‑1 or
Climate Control Systems (with
Heater Only) on page 8‑4 orDual
Automatic Climate Control System
on page 8‑5 for more information.
Park Tilt Mirrors
If the vehicle has the memory
package, the passenger and/or
driver mirror tilts to a preselected
position when the vehicle is in
R (Reverse). This feature lets the
driver view the curb when parallel
parking. The mirror(s) return to the
original position when the vehicle is
shifted out of R (Reverse), or the
ignition is turned off or to
OFF/LOCK.
Turn this feature on or off through
the Driver Information Center (DIC).
SeeVehicle Personalization (With
DIC Buttons) on page 5‑48 for more
information.

Black plate (18,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
2-18 Keys, Doors, and Windows
Interior Mirrors
Manual Rearview Mirror
To adjust the inside rearview mirror,
hold the rearview mirror in the
center and move it to view the area
behind the vehicle.
For vehicles with a manual rearview
mirror, push the tab forward for
daytime use and pull it for nighttime
use to avoid glare from the
headlamps from behind.
Vehicles with OnStar
®have three
control buttons at the bottom of the
mirror. See a dealer for more
information about OnStar and how
to subscribe to it. See OnStar
Overview on page 14‑1.
Automatic Dimming
Rearview Mirror
The vehicle may have an automatic
dimming inside rearview mirror.
To adjust the inside rearview mirror,
hold the rearview mirror in the
center and move it to view the area
behind the vehicle.
The automatic dimming rearview
mirror will automatically reduce the
glare from the headlamps from
behind. The dimming feature comes
on when the vehicle is started.
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 9‑62
for more information. If the vehicle has a RVC,
the
Obutton for turning the
dimming feature on or off will
not be available.
Vehicles with OnStar have three
additional control buttons for the
OnStar system. See a dealer for
more information about OnStar and
how to subscribe to it. See OnStar
Overview on page 14‑1.
Cleaning the Mirror
Do not spray glass cleaner directly
on the mirror. Use a soft towel
dampened with water.

Black plate (19,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Keys, Doors, and Windows 2-19
Windows
{WARNING
Leaving children, helpless adults,
or pets in a vehicle with the
windows closed is dangerous.
They can be overcome by the
extreme heat and suffer
permanent injuries or even death
from heat stroke. Never leave a
child, a helpless adult, or a pet
alone in a vehicle, especially with
the windows closed in warm or
hot weather.
The vehicle aerodynamics are
designed to improve fuel economy
performance. This may result in apulsing sound when a window is
partially open. To reduce the sound,
open another window or the sunroof
(if equipped).
Manual Windows
Turn the hand crank on each door
to manually raise or lower the
manual windows.

Black plate (20,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
2-20 Keys, Doors, and Windows
Power Windows
{WARNING
Leaving children in a vehicle with
the keys is dangerous for many
reasons. Children or others could
be badly injured or even killed.
They could operate the power
windows or other controls or even
make the vehicle move. The
windows will function and they
could be seriously injured or killed
if caught in the path of a closing
window. Do not leave keys in a
vehicle with children.
When there are children in the
rear seat use the window lockout
button to prevent unintentional
operation of the windows.
Crew Cab Premium Trim Shown,Others Models Similar
The driver door has a switch
to control all windows. Each
passenger door has a switch to
control that window. The power
windows only work when the
ignition is in ON/RUN or ACC/
ACCESSORY, or when Retained
Accessory Power (RAP) is active.
See Retained Accessory Power
(RAP) on page 9‑29. Push the switch down to lower the
window, and pull up the front of the
switch to raise the window.
Express-down Windows
The express-down feature allow the
driver and front passenger windows
to be lowered without holding the
switch. Push the switch down to the
second detent, then release, to
activate the express-down mode.
The express-down mode can be
canceled at any time by pulling up
on the front of the switch. To open
the window partway, push the switch
down to the first detent until the
window is at the desired position.

Black plate (21,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Keys, Doors, and Windows 2-21
Window Lockout
Crew Cab Premium Trim Shown,Others Models Similar
o(Window Lockout): The driver
door power window switch has
a lockout feature. This feature
prevents the rear windows from
operating, except from the driver
position. Press the switch to engage
or disengage the lockout feature.
An indicator light on the switch will
come on when the lockout feature is
engaged, and will go off when
disengaged.
Rear Windows
Power Sliding Rear Window
If equipped, the power sliding rear
window works when the ignition has
been turned to ACC/ACCESSORY
or ON/RUN, or when Retained
Accessory Power (RAP) is active. See
Retained Accessory Power
(RAP) on page 9‑29 for more
information.
.Push the switch to open the
window.
.Pull the switch to close the
window.
The power sliding rear window
cannot be operated manually.
Sun Visors
Pull the sun visor down to block
glare. Detach the sun visor from the
center mount to pivot to the side
window, or to extend along the rod,
if available.

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.

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.

Black plate (24,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
2-24 Keys, Doors, and Windows
2NOTES

Black plate (1,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Seats and Restraints 3-1
Seats and
Restraints
Head Restraints
Head Restraints . . . . . . . . . . . . . . . 3-2
Front Seats
Seat Adjustment . . . . . . . . . . . . . . 3-3
Center Seat . . . . . . . . . . . . . . . . . . . 3-4
Power Seat Adjustment . . . . . . . 3-4
Lumbar Adjustment . . . . . . . . . . . 3-4
Reclining Seatbacks . . . . . . . . . . 3-5
Memory Seats . . . . . . . . . . . . . . . . 3-7
Heated and Ventilated FrontSeats . . . . . . . . . . . . . . . . . . . . . . . . 3-9
Rear Seats
Rear Seats (Extended CabFull Bench) . . . . . . . . . . . . . . . . . 3-10
Rear Seats (All Split Bench and Hybrid Full Bench) . . . . . 3-11
Safety Belts
Safety Belts . . . . . . . . . . . . . . . . . . 3-12
How to Wear Safety BeltsProperly . . . . . . . . . . . . . . . . . . . . 3-13
Lap-Shoulder Belt . . . . . . . . . . . 3-14 Safety Belt Use During
Pregnancy . . . . . . . . . . . . . . . . . . 3-19
Lap Belt (Crew and Extended Cab) . . . . . . . . . . . . . 3-19
Safety Belt Extender . . . . . . . . . 3-20
Safety System Check . . . . . . . . 3-20
Safety Belt Care . . . . . . . . . . . . . 3-20
Replacing Safety Belt System
Parts after a Crash . . . . . . . . . 3-21
Airbag System
Airbag System . . . . . . . . . . . . . . . 3-21
Where Are the Airbags? . . . . . 3-23
When Should an AirbagInflate? . . . . . . . . . . . . . . . . . . . . . 3-25
What Makes an Airbag Inflate? . . . . . . . . . . . . . . . . . . . . . 3-27
How Does an Airbag Restrain? . . . . . . . . . . . . . . . . . . . 3-27
What Will You See after an Airbag Inflates? . . . . . . . . . . . . 3-27
Airbag On-Off Switch . . . . . . . . 3-29
Passenger Sensing System . . . . . . . . . . . . . . . . . . . . . 3-32
Servicing the Airbag-Equipped Vehicle . . . . . . . . . . . . . . . . . . . . . 3-36 Adding Equipment to the
Airbag-Equipped Vehicle . . . 3-37
Airbag System Check . . . . . . . . 3-38
Replacing Airbag System Parts after a Crash . . . . . . . . . 3-38
Child Restraints
Older Children . . . . . . . . . . . . . . . 3-39
Infants and Young
Children . . . . . . . . . . . . . . . . . . . . 3-41
Child Restraint Systems . . . . . 3-44
Where to Put the Restraint . . . 3-45
Lower Anchors and Tethers for Children (LATCH
System) . . . . . . . . . . . . . . . . . . . . 3-47
Replacing LATCH System Parts After a Crash . . . . . . . . . 3-55
Securing Child Restraints (Rear Seat Position) . . . . . . . . 3-55
Securing Child Restraints (Center Front Seat
Position) . . . . . . . . . . . . . . . . . . . 3-58
Securing Child Restraints (Right Front Seat
Position) . . . . . . . . . . . . . . . . . . . 3-58

Black plate (2,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
3-2 Seats and Restraints
Head Restraints
Front Seats
The front seats have adjustable
head restraints in the outboard
seating positions.
{WARNING
With head restraints that are not
installed and adjusted properly,
there is a greater chance that
occupants will suffer a neck/
spinal injury in a crash. Do not
drive until the head restraints for
all occupants are installed and
adjusted properly.
Adjust the head restraint so that the
top of the restraint is at the same
height as the top of the occupant's
head. This position reduces the
chance of a neck injury in a crash.The height of the head restraint can
be adjusted. Pull the head restraint
up to raise it. Try to move the head
restraint to make sure that it is
locked in place.
To lower the head restraint, press
the button, located on the top of the
seatback, and push the restraint
down. Try to move the head
restraint after the button is released
to make sure that it is locked in
place.
The front seat outboard head
restraints are not designed to be
removed.