service indicator GMC SIERRA 2013 Owner's Manual

Black plate (4,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
iv Introduction
Danger, Warnings, and
Cautions
Warning messages found on vehicle
labels and in this manual describe
hazards and what to do to avoid or
reduce them.
Dangerindicates a hazard with a
high level of risk which will result in
serious injury or death.
Warning orCaution indicates a
hazard that could result in injury or
death.
{WARNING
These mean there is something
that could hurt you or other
people. Notice:
This means there is
something that could result in
property or vehicle damage. This
would not be covered by the
vehicle's warranty.
A circle with a slash through it is a
safety symbol which means “Do
Not,” “Do not do this,” or“Do not let
this happen.”
Symbols
The vehicle has components and
labels that use symbols instead of
text. Symbols are shown along with
the text describing the operation or
information relating to a specific
component, control, message,
gauge, or indicator.
M: This symbol is shown when
you need to see your owner manual
for additional instructions or
information.
*: This symbol is shown when
you need to see a service manual
for additional instructions or
information.

Black plate (30,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
3-30 Seats and Restraints
To turn off the right front passenger
airbag, insert the ignition key into
the switch, push in, and move the
switch to the off position.
The word OFF or the off symbol will
come on in the passenger airbag
status indicator located in the
overhead console to let you know
that the right front passenger airbag
is off, after the system check is
completed. The airbag off light will
come on and stay on to let you
know that the right front passenger's
airbag is off. SeeAirbag On-Off
Light on page 5‑18.{WARNING
If the airbag readiness light ever
comes on and stays on, it means
that something may be wrong
with the airbag system. For
example, the right front
passenger airbag could inflate
even though the airbag on-off
switch is turned off.
To help avoid injury to yourself or
others, have the vehicle serviced
right away. See Airbag Readiness
Light on page 5‑17 for more
information, including important
safety information.
United States
Canada and Mexico

Black plate (33,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
Seats and Restraints 3-33
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 5‑17 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 3‑56 orSecuring Child
Restraints (Right Front Seat
Position) on page 3‑57 or
Securing Child Restraints (Rear
Seat Position) on page 3‑54.
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.
Also make sure the child
restraint is not trapped under the
vehicle head restraint. If this
happens, adjust the head
restraint. See Head Restraints
on page 3‑2.

Black plate (35,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
Seats and Restraints 3-35
operates. We recommend that you
not use seat covers or other
aftermarket equipment except when
approved by GM for your specific
vehicle. SeeAdding Equipment to
the Airbag-Equipped Vehicle on
page 3‑35 for more information
about modifications that can affect
how the system operates.
The on indicator may be lit if an
object, such as a briefcase,
handbag, grocery bag, laptop or
other electronic device, is put on an
unoccupied seat. If this is not
desired, remove the object from
the seat.
{WARNING
Stowing of articles under the
passenger seat or between the
passenger seat cushion and
seatback may interfere with the
proper operation of the passenger
sensing system.
Servicing the
Airbag-Equipped Vehicle
Airbags affect how the vehicle
should be serviced. There are parts
of the airbag system in several
places around the vehicle. Your
dealer and the service manual have
information about servicing the
vehicle and the airbag system. To
purchase a service manual, see
Service Publications Ordering
Information on page 13‑16.
{WARNING
For up to 10 seconds after the
vehicle is turned off and the
battery is disconnected, an airbag
can still inflate during improper
service. You can be injured if you
are close to an airbag when it
inflates. Avoid yellow connectors.
(Continued)
WARNING (Continued)
They are probably part of the
airbag system. Be sure to follow
proper service procedures, and
make sure the person performing
work for you is qualified to do so.
Adding Equipment to the
Airbag-Equipped Vehicle
Q: Is there anything I might addto or change about the vehicle
that could keep the airbags
from working properly?
A: Yes. If you add things that
change your vehicle's frame,
bumper system, height, front end
or side sheet metal, they may
keep the airbag system from
working properly. Changing or
moving any parts of the front
seats, safety belts, the airbag
sensing and diagnostic module,
steering wheel, instrument
panel, roof-rail airbag modules,

Black plate (61,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
Seats and Restraints 3-61
{WARNING
If the airbag readiness light ever
comes on and stays on, it means
that something may be wrong
with the airbag system. For
example, the right front
passenger airbag could inflate
even though the airbag on-off
switch is turned off.
To help avoid injury to yourself or
others, have the vehicle serviced
right away. SeeAirbag Readiness
Light on page 5‑17 for more
information, including important
safety 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 3‑45 for how and
where to install the child restraint
using LATCH. If a child restraint is
secured using a safety belt and it
uses a top tether, see Lower
Anchors and Tethers for Children
(LATCH System) on page 3‑45 for
top tether anchor locations.
Do not secure a child restraint 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.
You will be using the lap-shoulder
belt to secure the child restraint in
this position. Follow the instructions
that came with the child restraint. 1. Move the seat as far back as it
will go before securing the
forward-facing child restraint.
If you have no other choice but
to install a rear-facing child
restraint in this seat, make sure
the airbag is off once the child
restraint has been installed.
When the airbag off switch has
turned off the right front
passenger frontal airbag, the off
indicator in the airbag off light
should light and stay lit when
you start the vehicle. See Airbag
On-Off Light on page 5‑18.
2. Put the child restraint on the seat.
3. Pick up the latch plate, and run the lap and shoulder portions of
the vehicle's safety belt through
or around the restraint. The child
restraint instructions will show
you how.

Black plate (16,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
5-16 Instruments and Controls
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 5‑20 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
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 may 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.
Passenger Safety Belt
Reminder Light
There may be a passenger safety
belt reminder light near the
passenger airbag status indicator.
See
Passenger Sensing System on
page 3‑31.

Black plate (19,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
Instruments and Controls 5-19
{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 identified
by the national government. See
Airbag On-Off Switch on
page 3‑28for more on this,
including important safety
information.
{WARNING
If the airbag readiness light ever
comes on and stays on, it means
that something may be wrong
with the airbag system. For
example, the right front
passenger airbag could inflate
even though the airbag on-off
switch is turned off.
To help avoid injury to yourself or
others, have the vehicle serviced
right away. See Airbag Readiness
Light on page 5‑17 for more
information, including important
safety information.
If the word ON or the on symbol is
lit, it means that the right front
passenger frontal airbag is enabled
(may inflate). See Airbag On-Off
Switch on page 3‑28 for more
information, including important
safety information. 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 airbag
on-off switch. See your dealer for
service.
Passenger Airbag Status
Indicator
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. See
Airbag On-Off Switch
on page 3‑28.
The passenger airbag status
indicator is on the overhead
console. See Passenger Sensing
System on page 3‑31 for important
safety information.

Black plate (20,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
5-20 Instruments and Controls
In addition, if the vehicle has a
passenger sensing system for the
right front passenger position, the
label on the vehicle's sun visor
refers to“ADVANCED AIRBAGS”.
United States
Canada and Mexico
When the vehicle is started, the
passenger airbag status indicator
will light ON and OFF, or the symbol
for on and off, for several seconds
as a system check. Then, after
several more seconds, the status
indicator will light either ON or OFF, or either the on or off symbol to let
you know the status of the right front
passenger frontal airbag.
If the word ON or the on symbol is
lit on the passenger airbag status
indicator, it means that the right
front passenger frontal airbag is
enabled (may inflate).
If the word OFF or the off symbol is
lit on the airbag status indicator, it
means that the passenger sensing
system has turned off the right front
passenger frontal airbag.
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
(Continued)
WARNING (Continued)
with the airbag system. To help
avoid injury to yourself or others,
have the vehicle serviced right
away. SeeAirbag Readiness
Light on page 5‑17 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.

Black plate (21,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
Instruments and Controls 5-21
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 5‑37for 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, helping to
maintain a clean environment. The
malfunction indicator lamp 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 9‑24.
If the malfunction indicator lamp
comes on while the engine is
running, this indicates that the OBD
II system has detected a problem
and diagnosis and service might be
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 also
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

Black plate (24,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
5-24 Instruments and Controls
MetricEnglish
This light comes on briefly when the
ignition key is turned to ON/RUN.
If it does not come on then, have it
fixed so it is ready to warn if there is
a problem.
{WARNING
The brake system might not be
working properly if the brake
system warning light is on.
Driving with the brake system
warning light on can lead to a
crash. If the light is still on after
the vehicle has been pulled off
the road and carefully stopped,
have the vehicle towed for
service. If the light comes on while driving,
pull off the road and stop carefully.
The pedal might be harder to push
or might go closer to the floor. It can
take longer to stop. If the light is still
on, have the vehicle towed for
service. See
Towing the Vehicle on
page 10‑87.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
Antilock Brake System
(ABS) Warning Light
For vehicles with the Antilock Brake
System (ABS), this light comes on
briefly when the engine is started. If it does not, have the vehicle
serviced by your dealer. If the
system is working normally the
indicator light then goes off.
If the ABS light stays on, turn the
ignition off. If the light comes on
while driving, stop as soon as it is
safely possible and turn the ignition
off. Then start the engine again to
reset the system. If the ABS light
stays on, or comes on again while
driving, the vehicle needs service.
If the regular brake system warning
light is not on, the vehicle still has
brakes, but not antilock brakes.
If the regular brake system warning
light is also on, the vehicle does not
have antilock brakes and there is a
problem with the regular brakes.
See
Brake System Warning Light on
page 5‑23.
For vehicles with a Driver
Information Center (DIC), see Brake
System Messages on page 5‑38 for
all brake‐related DIC messages.