Page 23 of 556

Black plate (17,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
In Brief 1-17
Exterior Mirrors
Power Mirrors
Crew Cab Premium Trim with
Power Folding Mirrors Shown, Up-Level Similar
1. Press (A) or (B) to select the driver or passenger side mirror.
2. Press the arrows on the control pad to move the mirror up,
down, right, or left. 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.
See Power Mirrors on page 2‑15.
If the vehicle has power folding
mirrors:
1. Press (C) to fold the mirrors out to the driving position.
2. Press (D) to fold the mirrors in to the folded position.
See Folding Mirrors on page 2‑16.
The mirrors may also include a
memory function that works with the
memory seats. See Memory Seats
on page 3‑7 for more information.
Crew Cab Up-Level Trim without
Power Folding Mirrors
1. Move the selector switch located above the four-way control pad
to the left or right to choose
either the driver side or
passenger side mirror.
2. Press one of the four arrows located on the control pad to
move the mirror in the desired
direction.
3. Adjust each outside mirror so that a little of the vehicle and the
area behind it can be seen.
Page 59 of 556

Black plate (15,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Keys, Doors, and Windows 2-15
Trailer-Tow 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.
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.
Power Mirrors
Crew Cab Premium Trim with
Power Folding Mirrors Shown, Other Models Similar
1. Press (A) or (B) to select the driver or passenger side mirror.
2. Press the arrows on the control pad to move the mirror up,
down, right, or left.
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 Seats
on page 3‑7 for more information.
Crew Cab Up‐Level Trim without
Power Folding Mirrors
1. Move the selector switch located above the four-way control pad
to the left or right to choose
either the driver side or
passenger side mirror.
Page 60 of 556

Black plate (16,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
2-16 Keys, Doors, and Windows
2. Press one of the four arrowslocated on the control pad to
move the mirror in the desired
direction.
3. Adjust each outside mirror so that a little of the vehicle and the
area behind it can be seen.
Keep the selector switch in the
center position when not adjusting
either outside mirror.Folding Mirrors
Crew Cab Premium Trim with
Power Folding Mirrors Shown, Other Models Similar
Power Folding
If equipped with power folding
mirrors:
1. Press (A) to fold the mirrors outto the driving position.
2. Press (B) to fold the mirrors in to the folded position. The mirrors may also include a
memory function that works with the
memory seats. See
Memory Seats
on page 3‑7 for more information.
Resetting the Power Folding
Mirrors
Reset the power folding mirrors if:
.The mirrors are accidentally
obstructed while folding.
.They are accidentally manually
folded/unfolded.
.The mirrors will not stay in the
unfolded position.
.The mirrors vibrate at normal
driving speeds.
Fold and unfold the mirrors one time
using the mirror controls to reset
them to their normal position.
A popping noise may be heard
during the resetting of the power
folding mirrors. This sound is normal
after a manual folding operation.
Page 72 of 556
Black plate (4,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
3-4 Seats and Restraints
Center Seat
If equipped, the center front
seatback doubles as an armrest and
cupholder/storage area for the driver
and passenger when the center
front seat is not used. Do not use it
as a seating position when the
seatback is folded down.
Power Seat Adjustment
To adjust a power seat, if equipped:
.Move the seat forward or
rearward by sliding the control
forward or rearward.
.If available, raise or lower the
front or rear part of the seat
cushion by moving the front or
rear of the control up or down.
.If available, raise or lower the
entire seat by moving the entire
control up or down.To adjust the seatback, see
“Power
Reclining Seatbacks” under
Reclining Seatbacks on page 3‑5.
Lumbar Adjustment
Manual Lumbar
If equipped, increase or decrease
manual lumbar support by turning
the knob forward or rearward.
Page 74 of 556
Black plate (6,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
3-6 Seats and Restraints
Manual Reclining Seatbacks
{WARNING
If either seatback is not locked, it
could move forward in a sudden
stop or crash. That could cause
injury to the person sitting there.
Always push and pull on the
seatbacks to be sure they are
locked.
To adjust a manual seatback:
1. Lift the lever.The seatback will automatically
fold forward.
2. To recline, move the seatback rearward to the desired position,
then release the lever to lock the
seatback in place.
3. Push and pull on the seatback to make sure it is locked. To return the seatback to the upright
position:
1. Lift the lever fully without
applying pressure to the
seatback, and the seatback will
return to the upright position.
2. Push and pull on the seatback to make sure it is locked.
Page 78 of 556

Black plate (10,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
3-10 Seats and Restraints
Remote Start Heated Seats
When it is cold outside, the heated
seats may turn on automatically
during a remote vehicle start. The
heated seats will be canceled when
the ignition is turned on. Press the
desired button to use the heated
seats after the vehicle is started.
The lights on the heated seat
buttons do not turn on during a
remote start.
The temperature performance of an
unoccupied seat may be reduced.
This is normal.
SeeRemote Vehicle Start on
page 2‑5.Rear Seats
Rear Seats (Extended
Cab Full Bench)
Folding the Rear Seat
Notice: Folding a rear seat with
the safety belts still fastened may
cause damage to the seat or the
safety belts. Always unbuckle the
safety belts and return them to
their normal stowed position
before folding a rear seat.
To fold the seat:
1. Pull up on the front of the seat cushion while pulling down on
the release strap under the seat
cushion.
2. Pull the seat cushion up until it latches with the seatback.
3. Pull forward on the seat cushion to make sure it is locked in
place.
Page 79 of 556

Black plate (11,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Seats and Restraints 3-11
To unfold the seat:
1. Push the seat cushion rearwardwhile pulling the release strap
under the seat cushion. Pull the
seat cushion down until it
latches.
2. Pull up on the seat cushion to make sure it is locked in place.
Make sure the safety belts are
not twisted or caught in the seat
cushion.
{WARNING
A safety belt that is improperly
routed, not properly attached,
or twisted will not provide the
protection needed in a crash. The
person wearing the belt could be
seriously injured. After raising the
rear seatback, always check to be
sure that the safety belts are
properly routed and attached, and
are not twisted.
Rear Seats (All Split
Bench and Hybrid Full
Bench)
Folding Rear Seat
Either side of the rear seat can be
folded for added cargo space.
Notice: Folding a rear seat with
the safety belts still fastened may
cause damage to the seat or the
safety belts. Always unbuckle the
safety belts and return them to
their normal stowed position
before folding a rear seat.
Make sure that nothing is on
the seat.
To fold the seat, slowly pull the seat
cushion up. To return the seat to the normal
seating position, slowly pull the seat
cushion down.
Make sure the safety belts are not
twisted or caught in the seat
cushion.
{WARNING
A safety belt that is improperly
routed, not properly attached,
or twisted will not provide the
protection needed in a crash. The
person wearing the belt could be
seriously injured. After raising the
rear seatback, always check to
be sure that the safety belts are
properly routed and attached, and
are not twisted.
Page 120 of 556

Black plate (52,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
3-52 Seats and Restraints
{WARNING
Children can be seriously injured
or strangled if a shoulder belt is
wrapped around their neck and
the safety belt continues to
tighten. Buckle any unused safety
belts behind the child restraint so
children cannot reach them. Pull
the shoulder belt all the way out
of the retractor to set the lock,
if the vehicle has one, after the
child restraint has been installed.
Notice: Do not let the LATCH
attachments rub against the
vehicle’ s safety belts. This may
damage these parts. If necessary,
move buckled safety belts to
avoid rubbing the LATCH
attachments.
Do not fold the empty rear seat
with a safety belt buckled. This
could damage the safety belt or
the seat. Unbuckle and return the
safety belt to its stowed position,
before folding the seat. Regular Cab Models
1. If the child restraint manufacturer
recommends that the top tether
be attached, attach and tighten
the top tether to the top tether
anchor, if your vehicle has one.
Refer to the child restraint
instructions and the following
steps:
1.1. Pull the passenger seatback forward by pulling
the recliner handle upward
to access the top tether
anchor. See Reclining
Seatbacks on page 3‑5 for
additional information.
1.2. Find the top tether anchor.
1.3. Remove the cover to expose the anchor. 1.4. Route, attach, and tighten
the top tether according
to your child restraint
instructions and the
following instructions:
If the position you are using
has an adjustable headrest
or head restraint and you
are using a dual tether,
route the tether around the
headrest or head restraint.