air condition GMC SIERRA 1500 2012 User Guide

Black plate (17,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Seats and Restraints 3-17
After you move the adjuster to
where you want it, try to move it
down, without squeezing the buttons
for the regular and crew cabs,
or without pushing the release
button for extended cabs, to make
sure it has locked into position.
Safety Belt Pretensioners
This vehicle has safety belt
pretensioners for front outboard
occupants. Although the safety belt
pretensioners cannot be seen, they
are part of the safety belt assembly.
They can help tighten the safety
belts during the early stages of a
moderate to severe frontal, near
frontal, or rear crash if the threshold
conditions for pretensioner
activation are met. And, if your
vehicle has side impact airbags,
safety belt pretensioners can help
tighten the safety belts in a side
crash or a rollover event.Pretensioners work only once. If the
pretensioners activate in a crash,
they will need to be replaced, and
probably other new parts for the
vehicle's safety belt system. See
Replacing Safety Belt System Parts
after a Crash on page 3‑21.
Rear Safety Belt Comfort
Guides
This vehicle may have rear shoulder
belt comfort guides. If not, they are
available through your dealer. The
guides may provide added safety
belt comfort for older children who
have outgrown booster seats and
for some adults. When installed and
properly adjusted, the comfort guide
positions the belt away from the
neck and head.
Here is how to install a comfort
guide to the shoulder belt:
1. Remove the guide from its
storage clip on the interior body.
2. Place the guide over the beltand insert the two edges of the
belt into the slots of the guide.

Black plate (29,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Seats and Restraints 3-29
other parts. The service manual
for your vehicle covers the need
to replace other parts.
.The vehicle has a crash sensing
and diagnostic module which
records information after a
crash. SeeVehicle Data
Recording and Privacy on
page 13‑19 andEvent Data
Recorders on page 13‑19.
.Let only qualified technicians
work on the airbag systems.
Improper service can mean that
an airbag system will not work
properly. See your dealer for
service.
Airbag On-Off Switch
If one of the switches pictured in the
following illustrations is located in
the glove box, the vehicle has an
airbag on-off switch that you can
use to manually turn on or off the
right front passenger airbag.
United States
Canada and Mexico If the vehicle does not have an
airbag off switch, it may have a
passenger sensing system. See
Passenger Sensing System on
page 3‑32.
This switch should only be turned to
the off position if the person in the
right front passenger position is a
member of a passenger risk
group identified by the national
government as follows:
Infant. An infant (less than 1 year
old) must ride in the front seat
because:
.My vehicle has no rear seat;
.My vehicle has a rear seat too
small to accommodate a
rear-facing infant seat; or
.The infant has a medical
condition which, according to
the infant's physician, makes it
necessary for the infant to ride in
the front seat so that the driver
can constantly monitor the
child's condition.

Black plate (30,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
3-30 Seats and Restraints
Child age 1 to 12. A child
age 1 to 12 must ride in the front
seat because:
.My vehicle has no rear seat;
.Although children ages 1 to 12
ride in the rear seat(s) whenever
possible, children ages 1 to 12
sometimes must ride in the front
because no space is available in
the rear seat(s) of my vehicle; or
.The child has a medical
condition which, according to
the child's physician, makes it
necessary for the child to ride in
the front seat so that the driver
can constantly monitor the
child's condition.
Medical Condition. A passenger
has a medical condition which,
according to his or her physician:
.Causes the passenger airbag to
pose a special risk for the
passenger; and
.Makes the potential harm from
the passenger airbag in a crash
greater than the potential harm from turning off the airbag and
allowing the passenger, even if
belted, to hit the instrument
panel or windshield in a crash.
{WARNING
If the right front passenger airbag
is turned off for a person who is
not in a risk group identified by
the national government, that
person will not have the extra
protection of an airbag. In a
crash, the airbag will not be able
to inflate and help protect the
person sitting there. Do not turn
off the passenger airbag unless
the person sitting there is in a risk
group.
United States
Canada and Mexico

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 (38,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
3-38 Seats and Restraints
Q: What if I added a snow plow?Will it keep the airbags from
working properly?
A: We have designed our airbag
systems to work properly under
a wide range of conditions,
including snow plowing with
vehicles that have the optional
Snow Plow Prep Package
(RPO VYU). But do not change
or defeat the snow plow's
“tripping mechanism.” If you do,
it can damage your snow plow
and your vehicle, and it may
cause an airbag inflation.
Q: Because I have a disability, I have to get my vehicle
modified. How can I find out
whether this will affect my
airbag system?
A: If you have questions, call
Customer Assistance. The
phone numbers and addresses
for Customer Assistance are
in Step Two of the Customer
Satisfaction Procedure in
this manual. See Customer Satisfaction Procedure (U.S.
and Canada) on page 13‑3
or
Customer Satisfaction
Procedure (Mexico) on
page 13‑3.
In addition, your dealer and the
service manual have information
about the location of the airbag
sensors, sensing and diagnostic
module and airbag wiring.
Airbag System Check
The airbag system does not need
regularly scheduled maintenance or
replacement. Make sure the airbag
readiness light is working. See
Airbag Readiness Light on
page 5‑18.
Notice: If an airbag covering is
damaged, opened, or broken, the
airbag may not work properly. Do
not open or break the airbag
coverings. If there are any
opened or broken airbag covers,
have the airbag covering and/or
airbag module replaced. For
the location of the airbags, see Where Are the Airbags? on
page 3‑23. See your dealer for
service.
Replacing Airbag System
Parts after a Crash
{WARNING
A crash can damage the
airbag systems in the vehicle.
A damaged airbag system
may not work properly and
may not protect you and your
passenger(s) in a crash, resulting
in serious injury or even death.
To help make sure the airbag
systems are working properly
after a crash, have them
inspected and any necessary
replacements made as soon as
possible.

Black plate (58,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
3-58 Seats and Restraints
6. If the child restraint has a toptether, follow the child restraint
manufacturer's instructions
regarding the use of the top
tether. See Lower Anchors and
Tethers for Children (LATCH
System) on page 3‑47 for more
information.
7. Before placing a child in the child restraint, make sure it is
securely held in place. To
check, grasp the child restraint
at the safety belt path and
attempt to move it side‐to‐side
and back‐and‐forth. When
the child restraint is properly
installed, there should be no
more than 2.5 cm (1 in) of
movement.
To remove the child restraint,
unbuckle the vehicle safety belt and
let it return to the stowed position.
If the top tether is attached to a top
tether anchor, disconnect it.Securing Child Restraints
(Center Front Seat
Position)
{WARNING
A child in a child restraint in the
center front seat can be badly
injured or killed by the frontal
airbags if they inflate. Never
secure a child restraint in the
center front seat. It is always
better to secure a child restraint in
a rear seat.
Do not use child restraints in the
center front seat position.
Securing Child Restraints
(Right Front Seat
Position)
With Passenger Sensing
System
This vehicle has airbags. A rear
seat is a safer place to secure a
forward-facing child restraint. See
Where to Put the Restraint on
page 3‑45.
In addition, the vehicle may have a
passenger sensing system which is
designed to turn off the right front
passenger frontal airbag under
certain conditions. See Passenger
Sensing System on page 3‑32 and
Passenger Airbag Status Indicator
on page 5‑21 for more information
on this, including important safety
information.
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.

Black plate (59,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Seats and Restraints 3-59
{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
passenger airbag inflates and the
passenger seat is in a forward
position.
The vehicle may have a
passenger sensing system which
is designed to turn off the right
front passenger frontal airbag
under certain conditions.
Even if the passenger sensing
system, if equipped, has turned
off the right front passenger
frontal airbag, no system is(Continued)
WARNING (Continued)
fail-safe. No one can
guarantee that an airbag will
not deploy under some unusual
circumstance, even though it 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.
SeePassenger Sensing System
on page 3‑32 for additional
information.
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. If the child restraint has the LATCH
system, see
Lower Anchors and
Tethers for Children (LATCH
System) on page 3‑47 for how and
where to install the child restraint
using LATCH. If you secure a child
restraint using a safety belt and it
uses a top tether, see Lower
Anchors and Tethers for Children
(LATCH System) on page 3‑47 for
top tether anchor locations.
Do not secure a child seat in a
position without a top tether anchor
if a national or local law requires
that the top tether be anchored, or if
the instructions that come with the
child restraint say that the top strap
must be anchored.
In Canada, the law requires that
forward-facing child restraints have
a top tether, and that the tether be
attached.

Black plate (17,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Instruments and Controls 5-17
When the engine is running, this
gauge shows the condition of the
charging system. The gauge can
transition from a higher to lower or a
lower to higher reading. This is
normal. If the vehicle is operating
outside the normal operating range,
the charging system light comes on.
SeeCharging System Light on
page 5‑22 for more information. The
voltmeter gauge may also read
lower when in fuel economy mode.
This is normal.
Readings outside the normal
operating range can also occur
when a large number of electrical
accessories are operating in the
vehicle and the engine is left idling
for an extended period. This
condition is normal since the
charging system is not able to
provide full power at engine idle. As engine speeds are increased,
this condition should correct itself as
higher engine speeds allow the
charging system to create maximum
power.
The vehicle can only be driven for a
short time with the readings outside
the normal operating range. If the
vehicle must be driven, turn off all
accessories, such as the radio and
air conditioner.
Readings outside the normal
operating range indicate a possible
problem in the electrical system.
Have the vehicle serviced as soon
as possible.Safety Belt Reminders
Driver Safety Belt Reminder
Light
There is a driver safety belt
reminder light on the instrument
panel cluster.
When the vehicle is started, this
light flashes and a chime may come
on to remind the driver to fasten
their safety belt. Then the light stays
on solid until the belt is buckled.
This cycle my continue several
times if the driver remains or
becomes unbuckled while the
vehicle is moving.
If the driver safety belt is buckled,
neither the light nor the chime
comes on.

Black plate (22,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
5-22 Instruments and Controls
If, after several seconds, both status
indicator lights remain on, or if there
are no lights at all, there may be a
problem with the lights or the
passenger sensing system. See
your dealer for service.
{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. SeeAirbag Readiness
Light on page 5‑18 for more
information, including important
safety information.
Charging System Light
This light comes on briefly when the
ignition key is turned to START, but
the engine is not running, as a
check to show it is working.
If it does not, have the vehicle
serviced by your dealer.
The light should go out once
the engine starts. If it stays on,
or comes on while driving, there
could be a problem with the
charging system. A charging system
message in the Driver Information
Center (DIC) can also appear. See
Battery Voltage and Charging
Messages on page 5‑39 for more
information. This light could indicate
that there are problems with a
generator drive belt, or that there
is an electrical problem. Have it checked right away. If the vehicle
must be driven a short distance with
the light on, turn off accessories,
such as the radio and air
conditioner.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.Malfunction
Indicator Lamp
A computer system called OBD II
(On-Board Diagnostics-Second
Generation) monitors the operation
of the vehicle to ensure emissions
are at acceptable levels, to produce
a cleaner environment. This light
comes on when the vehicle is
placed in ON/RUN, as a check to
show it is working. If it does not,
have the vehicle serviced by your
dealer. See
Ignition Positions on
page 9‑26.

Black plate (23,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Instruments and Controls 5-23
If the malfunction indicator lamp
comes on and stays on while the
engine is running, this indicates that
there is an OBD II problem and
service is required.
Malfunctions often are indicated by
the system before any problem is
apparent. Being aware of the light
can prevent more serious damage
to the vehicle. This system assists
the service technician in correctly
diagnosing any malfunction.
Notice:If the vehicle is
continually driven with this light
on, the emission controls might
not work as well, the vehicle fuel
economy might not be as good,
and the engine might not run as
smoothly. This could lead to
costly repairs that might not be
covered by the vehicle warranty. Notice:
Modifications made
to the engine, transmission,
exhaust, intake, or fuel system
of the vehicle or the replacement
of the original tires with other
than those of the same Tire
Performance Criteria (TPC) can
affect the vehicle's emission
controls and can cause this light
to come on. Modifications to
these systems could lead to
costly repairs not covered by
the vehicle warranty. This could
also result in a failure to pass a
required Emission Inspection/
Maintenance test. See
Accessories and Modifications on
page 10‑3.
This light comes on during a
malfunction in one of two ways:
Light Flashing: A misfire condition
has been detected. A misfire
increases vehicle emissions and
could damage the emission control
system on the vehicle. Diagnosis
and service might be required. To prevent more serious damage to
the vehicle:
.Reduce vehicle speed.
.Avoid hard accelerations.
.Avoid steep uphill grades.
.If towing a trailer, reduce the
amount of cargo being hauled as
soon as it is possible.
If the light continues to flash, stop
and park the vehicle. Turn the
vehicle off, wait at least 10 seconds,
and restart the engine. If the light is
still flashing, follow the previous
steps and see your dealer for
service as soon as possible.
Light On Steady: An emission
control system malfunction has
been detected on the vehicle.
Diagnosis and service might be
required.