ECU GMC SIERRA 1500 2012 User Guide

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 (15,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Seats and Restraints 3-15
Engaging the child restraint
locking feature may affect the
passenger sensing system,
if equipped. SeePassenger
Sensing System on page 3‑32
for more information.
If the belt stops before it reaches
the buckle, when using the
lap-shoulder belt in a rear center
seating position of a crew-cab,
tilt the latch plate and keep
pulling the safety belt until it can
be buckled.
3. Push the latch plate into the buckle until it clicks.
Pull up on the latch plate to
make sure it is secure. If the belt
is not long enough, see Safety
Belt Extender on page 3‑20.
If the latch plate will not go fully
into the buckle, check if the
correct buckle is being used.
Position the release button on
the buckle so that the safety belt
could be quickly unbuckled if
necessary. 4. If equipped with a shoulder belt
height adjuster, move it to the
height that is right for you. See
“Shoulder Belt Height Adjuster”
later in this section.
5. To make the lap part tight, pull
up on the shoulder belt.
It may be necessary to pull
stitching on the safety belt
through the latch plate to fully
tighten the lap belt on smaller
occupants.

Black plate (20,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
3-20 Seats and Restraints
To make the belt shorter, pull its free
end as shown until the belt is snug.
If the belt is not long enough, see
Safety Belt Extender on page 3‑20.
Make sure the release button on the
buckle is positioned so you would
be able to unbuckle the safety belt
quickly if necessary.
Safety Belt Extender
If the vehicle's safety belt will fasten
around you, you should use it.
But if a safety belt is not long
enough, your dealer will order you
an extender. When you go in to
order it, take the heaviest coat you
will wear, so the extender will be
long enough for you. To help avoid
personal injury, do not let someone
else use it, and use it only for the
seat it is made to fit. The extender
has been designed for adults. Never
use it for securing child seats. To
wear it, attach it to the regular safety
belt. For more information, see the
instruction sheet that comes with
the extender.
Safety System Check
Now and then, check that the safety
belt reminder light, safety belts,
buckles, latch plates, retractors,
and anchorages are all working
properly. Look for any other loose or
damaged safety belt system parts
that might keep a safety belt systemfrom doing its job. See your dealer
to have it repaired. Torn or frayed
safety belts may not protect you in a
crash. They can rip apart under
impact forces. If a belt is torn or
frayed, get a new one right away.
Make sure the safety belt reminder
light is working. See
Safety Belt
Reminders on page 5‑17.
Keep safety belts clean and dry.
See Safety Belt Care on page 3‑20.
Safety Belt Care
Keep belts clean and dry.
{WARNING
Do not bleach or dye safety belts.
It may severely weaken them. In
a crash, they might not be able
to provide adequate protection.
Clean safety belts only with mild
soap and lukewarm water.

Black plate (23,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Seats and Restraints 3-23
{WARNING
Children who are up against,
or very close to, any airbag
when it inflates can be seriously
injured or killed. Airbags plus
lap-shoulder belts offer protection
for adults and older children, but
not for young children and infants.
Neither the vehicle safety belt
system nor its airbag system
is designed for them. Young
children and infants need the
protection that a child restraint
system can provide. Always
secure children properly in the
vehicle. To read how, seeOlder
Children on page 3‑39 orInfants
and Young Children on
page 3‑41.
There is an airbag readiness light
on the instrument panel cluster,
which shows the airbag symbol.
The system checks the airbag
electrical system for malfunctions.
The light tells you if there is an
electrical problem. See Airbag
Readiness Light on page 5‑18 for
more information.
Where Are the Airbags?
The driver airbag is in the middle of
the steering wheel.

Black plate (25,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Seats and Restraints 3-25
{WARNING
If something is between an
occupant and an airbag, the
airbag might not inflate properly
or it might force the object into
that person causing severe injury
or even death. The path of an
inflating airbag must be kept
clear. Do not put anything
between an occupant and an
airbag, and do not attach or put
anything on the steering wheel
hub or on or near any other
airbag covering.
Do not use seat accessories that
block the inflation path of a
seat-mounted side impact airbag.
Never secure anything to the roof
of a vehicle with roof-rail airbags
by routing a rope or tie‐down
through any door or window
opening. If you do, the path of an
inflating roof-rail airbag will be
blocked.
When Should an Airbag
Inflate?
Frontal airbags are designed to
inflate in moderate to severe frontal
or near-frontal crashes to help
reduce the potential for severe
injuries mainly to the driver's or right
front passenger's head and chest.
However, they are only designed
to inflate if the impact exceeds a
predetermined deployment
threshold. Deployment thresholds
are used to predict how severe a
crash is likely to be in time for the
airbags to inflate and help restrain
the occupants.
Whether the frontal airbags will
or should deploy is not based on
how fast your vehicle is traveling.
It depends largely on what you hit,
the direction of the impact, and how
quickly your vehicle slows down.Frontal airbags may inflate at
different crash speeds. For
example:.If the vehicle hits a stationary
object, the airbags could inflate
at a different crash speed than if
the vehicle hits a moving object.
.If the vehicle hits an object that
deforms, the airbags could
inflate at a different crash speed
than if the vehicle hits an object
that does not deform.
.If the vehicle hits a narrow object
(like a pole), the airbags could
inflate at a different crash speed
than if the vehicle hits a wide
object (like a wall).
.If the vehicle goes into an object
at an angle, the airbags could
inflate at a different crash speed
than if the vehicle goes straight
into the object.
Thresholds can also vary with
specific vehicle design.

Black plate (32,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
3-32 Seats and Restraints
Passenger Sensing
System
If the vehicle has one of the
indicators pictured in the following
illustrations, then the vehicle has a
passenger sensing system for the
right front passenger position,
unless there is an airbag off switch
located in the glove box. If there is
an airbag off switch, the vehicle
does not have a passenger sensing
system. SeeAirbag On-Off Switch
on page 3‑29 for more information.
The passenger airbag status
indicator will be visible on the
overhead console when the vehicle
is started.
In addition, if the vehicle has a
passenger sensing system for the
right front passenger position, the
label on the vehicle's sun visors
refers to “ADVANCED AIRBAGS”.
United States
Canada and Mexico
The words ON and OFF, or the
symbol for on and off, will be visible
during the system check. If you
are using remote start to start the
vehicle from a distance, if equipped,
you may not see the system
check. When the system check is
complete, either the word ON or
OFF, or the symbol for on or off, will
be visible. See Passenger Airbag
Status Indicator on page 5‑21. The passenger sensing system will
turn off the right front passenger
frontal airbag under certain
conditions. The driver airbag,
seat‐mounted side impact airbags
(if equipped), and the roof-rail
airbags (if equipped) are not
affected by the passenger sensing
system.
The passenger sensing system
works with sensors that are part
of the right front passenger seat
and safety belt. The sensors are
designed to detect the presence
of a properly-seated occupant
and determine if the right front
passenger frontal airbag should be
enabled (may inflate) or not.
According to accident statistics,
children are safer when properly
secured in a rear seat in the correct
child restraint for their weight
and size.

Black plate (33,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Seats and Restraints 3-33
We recommend that children be
secured in a rear seat, including:
an infant or a child riding in a
rear-facing child restraint; a child
riding in a forward-facing child seat;
an older child riding in a booster
seat; and children, who are large
enough, using safety belts.
A label on the sun visor says,
“Never put a rear-facing child seat
in the front.”This is because the risk
to the rear-facing child is so great,
if the airbag deploys.
{WARNING
A child in a rear-facing child
restraint can be seriously
injured or killed if the right front
passenger airbag inflates. This
is because the back of the
rear-facing child restraint would
be very close to the inflating
airbag. A child in a forward-facing
child restraint can be seriously
injured or killed if the right front
(Continued)
WARNING (Continued)
passenger airbag inflates and the
passenger seat is in a forward
position.
Even if the passenger sensing
system has turned off the right
front passenger frontal airbag, no
system is fail-safe. No one can
guarantee that an airbag will not
deploy under some unusual
circumstance, even though the
airbag is turned off.
Secure rear-facing child restraints
in a rear seat, even if the
airbag is off. If you secure a
forward-facing child restraint in
the right front seat, always move
the front passenger seat as far
back as it will go. It is better to
secure the child restraint in a
rear seat. If the vehicle does not have a rear
seat that will accommodate a
rear-facing child restraint, a
rear-facing child restraint should not
be installed in the vehicle, even if
the airbag is off.
The passenger sensing system is
designed to turn off the right front
passenger frontal airbag if:
.The right front passenger seat is
unoccupied.
.The system determines an infant
is present in a child restraint.
.A right front passenger takes
his/her weight off of the seat for
a period of time.
.Or, if there is a critical problem
with the airbag system or the
passenger sensing system.
When the passenger sensing
system has turned off the right front
passenger frontal airbag, the off
indicator will light and stay lit to
remind you that the airbag is off.
See Passenger Airbag Status
Indicator on page 5‑21.

Black plate (34,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
3-34 Seats and Restraints
The passenger sensing system is
designed to turn on (may inflate) the
right front passenger frontal airbag
anytime the system senses that a
person of adult size is sitting
properly in the right front
passenger seat.
When the passenger sensing
system has allowed the airbag to be
enabled, the on indicator will light
and stay lit to remind you that the
airbag is active.
For some children, including
children in child restraints, and for
very small adults, the passenger
sensing system may or may not
turn off the right front passenger
frontal airbag, depending upon the
person's seating posture and body
build. Everyone in your vehicle
who has outgrown child restraints
should wear a safety belt
properly—whether or not there is
an airbag for that person.{WARNING
If the airbag readiness light ever
comes on and stays on, it means
that something may be wrong
with the airbag system. To help
avoid injury to yourself or others,
have the vehicle serviced right
away. See Airbag Readiness
Light on page 5‑18 for more
information, including important
safety information.
If the On Indicator is Lit for a
Child Restraint
If a child restraint has been installed
and the on indicator is lit:
1. Turn the vehicle off.
2. Remove the child restraint from the vehicle. 3. Remove any additional items
from the seat such as blankets,
cushions, seat covers, seat
heaters, or seat massagers.
4. Reinstall the child restraint following the directions
provided by the child restraint
manufacturer and refer to
Securing Child Restraints
(Center Front Seat Position) on
page 3‑58 orSecuring Child
Restraints (Right Front Seat
Position) on page 3‑58 or
Securing Child Restraints (Rear
Seat Position) on page 3‑55.
5. If, after reinstalling the child restraint and restarting the
vehicle, the on indicator is still lit,
turn the vehicle off. Then slightly
recline the vehicle seatback
and adjust the seat cushion,
if adjustable, to make sure that
the vehicle seatback is not
pushing the child restraint into
the seat cushion.

Black plate (35,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Seats and Restraints 3-35
Also make sure the child
restraint is not trapped under the
vehicle head restraint. If this
happens, adjust the head
restraint. SeeHead Restraints
on page 3‑2.
6. Restart the vehicle. The passenger sensing system
may or may not turn off the
airbag for a child in a child
restraint depending upon the
child’s seating posture and body
build. It is better to secure the
child restraint in a rear seat.If the Off Indicator is Lit for an
Adult-Size Occupant
If a person of adult-size is sitting in
the right front passenger seat, but
the off indicator is lit, it could be
because that person is not sitting
properly in the seat. If this happens,
use the following steps to allow the system to detect that person and
enable the right front passenger
frontal airbag:
1. Turn the vehicle off.
2. Remove any additional material
from the seat, such as blankets,
cushions, seat covers, seat
heaters, or seat massagers.
3. Place the seatback in the fully upright position.
4. Have the person sit upright in the seat, centered on the seat
cushion, with legs comfortably
extended.
5. Restart the vehicle and have the person remain in this position for
two to three minutes after the on
indicator is lit.

Black plate (40,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
3-40 Seats and Restraints
.Does the lap belt fit low and
snug on the hips, touching the
thighs? If yes, continue. If no,
return to the booster seat.
.Can proper safety belt fit be
maintained for the length of the
trip? If yes, continue. If no,
return to the booster seat.
Q: What is the proper way to wear safety belts?
A: An older child should wear a
lap-shoulder belt and get the
additional restraint a shoulder
belt can provide. The shoulder
belt should not cross the face or
neck. The lap belt should fit
snugly below the hips, just
touching the top of the thighs.
This applies belt force to the
child's pelvic bones in a crash.
It should never be worn over the
abdomen, which could cause
severe or even fatal internal
injuries in a crash.
Also see “Rear Safety Belt Comfort
Guides” underLap-Shoulder Belt on
page 3‑14. According to accident statistics,
children and infants are safer
when properly restrained in a child
restraint system or infant restraint
system secured in a rear seating
position.
In a crash, children who are not
buckled up can strike other people
who are buckled up, or can be
thrown out of the vehicle. Older
children need to use safety belts
properly.
{WARNING
Never allow more than one child
to wear the same safety belt. The
safety belt cannot properly spread
the impact forces. In a crash, they
can be crushed together and
seriously injured. A safety belt
must be used by only one person
at a time.
{WARNING
Never allow a child to wear the
safety belt with the shoulder belt
behind their back. A child can be
seriously injured by not wearing
the lap-shoulder belt properly. In a
crash, the child would not be
restrained by the shoulder belt.
The child could move too far
forward increasing the chance of
head and neck injury. The child
might also slide under the lap
(Continued)