2013 GMC SIERRA wiring

Black plate (36,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
3-36 Seats and Restraints
ceiling headliner or pillar garnish
trim, overhead console, front
sensors, side impact sensors,
or airbag wiring can affect the
operation of the airbag system.
In addition, the vehicle may have
a passenger sensing system for
the right front passenger's
position, which includes sensors
that are part of the passenger's
seat. The passenger sensing
system may not operate properly
if the original seat trim is
replaced with non-GM covers,
upholstery or trim, or with GM
covers, upholstery or trim
designed for a different vehicle.
Any object, such as an
aftermarket seat heater or a
comfort enhancing pad or
device, installed under or on top
of the seat fabric, could also
interfere with the operation of
the passenger sensing system.This could either prevent proper
deployment of the passenger
airbag(s) or prevent the
passenger sensing system from
properly turning off the
passenger airbag(s). See
Passenger Sensing System on
page 3‑31.
If you have any questions about
this, you should contact
Customer Assistance before you
modify your vehicle. 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 13‑2 or
Customer Satisfaction
Procedure (Mexico) on
page 13‑4.
If the vehicle has rollover
roof-rail airbags, see Different
Size Tires and Wheels on
page 10‑66 for additional
important information. 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

Black plate (37,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
Seats and Restraints 3-37
Satisfaction Procedure in this
manual. SeeCustomer
Satisfaction Procedure (U.S. and
Canada) on page 13‑2 or
Customer Satisfaction
Procedure (Mexico) on
page 13‑4.
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 5‑17. 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 3‑22. 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
(Continued)
WARNING (Continued)
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.
If an airbag inflates, you will need to
replace airbag system parts. See
your dealer for service.
If the airbag readiness light stays on
after the vehicle is started or comes
on when you are driving, the airbag
system may not work properly. Have
the vehicle serviced right away. See
Airbag Readiness Light on
page 5‑17.

Black plate (17,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
Instruments and Controls 5-17
For vehicles equipped with the
passenger safety belt warning light,
when the vehicle is started this light
flashes and a chime may come on
to remind passengers to fasten their
safety belt. Then the light stays on
solid until the belt is buckled. This
cycle continues several times if the
passenger remains or becomes
unbuckled while the vehicle is
moving.
If the passenger safety belt is
buckled, neither the chime nor the
light comes on.
The front passenger safety belt
warning light and chime may turn on
if an object is put on the seat such
as a briefcase, handbag, grocery
bag, laptop, or other electronic
device. To turn off the warning light
and/or chime, remove the object
from the seat or buckle the
safety belt.Airbag Readiness Light
This light shows if there is an
electrical problem with the airbag
system. The system check includes
the airbag sensor(s), passenger
sensing system (if equipped), the
pretensioners, the airbag modules,
the wiring, and the crash sensing
and diagnostic module. For more
information on the airbag system,
seeAirbag System on page 3‑20.
The airbag readiness light comes on
for several seconds when the
vehicle is started. If the light does
not come on then, have it fixed
immediately.
{WARNING
If the airbag readiness light stays
on after the vehicle is started or
comes on while driving, it means
the airbag system might not be
working properly. The airbags in
the vehicle might not inflate in a
crash, or they could even inflate
without a crash. To help avoid
injury, have the vehicle serviced
right away.
If there is a problem with the airbag
system, a Driver Information Center
(DIC) message may also come on.
See Airbag System Messages on
page 5‑43.

Black plate (38,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
5-38 Instruments and Controls
could drain the battery. Turn off all
unnecessary accessories. Have the
electrical system checked as soon
as possible. See your dealer.
Brake System Messages
SERVICE BRAKE SYSTEM
This message displays along with
the brake system warning light if
there is a problem with the brake
system. SeeBrake System Warning
Light on page 5‑23. If this message
appears, stop as soon as possible
and turn off the vehicle. Restart the
vehicle and check for the message
on the DIC display. If the message
is still displayed or appears again
when you begin driving, the brake
system needs service as soon as
possible. See your dealer.
SERVICE BRAKES SOON
On some vehicles, this message
displays if there is a problem with
the brake system. If this message
appears, stop as soon as possible
and turn off the vehicle. Restart the vehicle and check for the message
on the DIC display. If the message
is still displayed or appears again
when you begin driving, the brake
system needs service. See your
dealer.
SERVICE TRAILER BRAKE
SYSTEM
On vehicles with the Integrated
Trailer Brake Control (ITBC) system,
this message displays and a chime
may sound when there is a problem
with the ITBC system.
When this message displays, power
is no longer available to the trailer
brakes.
As soon as it is safe to do so,
carefully pull your vehicle over to
the side of the road and turn the
ignition off. Check the wiring
connection to the trailer and turn the
ignition back on. If this message still
displays, either your vehicle or the
trailer needs service. See your
dealer.
See
“Integrated Trailer Brake
Control System” underTowing
Equipment on page 9‑89 for more
information.
Door Ajar Messages
DRIVER DOOR OPEN
This message displays and a chime
may sound if the driver door is not
fully closed and the vehicle is
shifted out of P (Park). Stop and turn
off the vehicle, check the door for
obstructions, and close the door
again. Check to see if the message
still appears on the DIC.
HOOD OPEN
This message displays and a chime
may sound if the hood is not fully
closed. Stop and turn off the
vehicle, check the hood for
obstructions, and close the hood
again. Check to see if the message
still appears on the DIC.

Black plate (45,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
Instruments and Controls 5-45
SERVICE 4 WHEEL DRIVE
If the vehicle has four-wheel drive,
this message may display if a
problem occurs with the
four-wheel-drive system. If this
message appears, stop as soon as
possible and turn off the vehicle.
Make sure the key is in the LOCK/
OFF position for at least one minute
and then restart the vehicle and
check for the message on the DIC
display. If the message is still
displayed or appears again when
you begin driving, the
four-wheel-drive system needs
service. See your dealer.
TRANSMISSION HOT IDLE
ENGINE
Notice:Do not drive the vehicle
while the transmission fluid is
overheating and the transmission
temperature warning is displayed
on the instrument cluster and/or
DIC, or the transmission can be
damaged. This could lead to
costly repairs that would not be
covered by the warranty. This message displays and a chime
may sound if the transmission fluid
in the vehicle gets hot. Driving with
the transmission fluid temperature
high can cause damage to the
vehicle. Stop the vehicle and let it
idle to allow the transmission to
cool. This message clears and the
chime stops when the fluid
temperature reaches a safe level.
Vehicle Reminder
Messages
CHECK TRAILER WIRING
On vehicles with the Integrated
Trailer Brake Control (ITBC) system,
this message may display and a
chime may sound when one of the
following conditions exists:
.A trailer with electric brakes
becomes disconnected from the
vehicle.
‐
If the disconnect occurs while
the vehicle is stopped, this
message clears itself after a
short time. ‐
If the disconnect occurs while
the vehicle is moving, this
message stays on until the
ignition is turned off.
.There is a short in the wiring to
the electric trailer brakes.
When this message displays, power
is no longer available to the trailer
brakes.
As soon as it is safe to do so,
carefully pull the vehicle over to the
side of the road and turn the ignition
off. Check the wiring connection to
the trailer and turn the ignition back
on. This message clears if the trailer
is reconnected. This message also
clears if you acknowledge it. If this
message still displays, either the
vehicle or the trailer needs service.
See your dealer.
See “Integrated Trailer Brake
Control System” underTowing
Equipment on page 9‑89 for more
information.

Black plate (6,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
6-6 Lighting
SIGNAL ON will also appear in the
Driver Information Control (DIC). To
turn the chime and message off,
move the turn signal lever to the off
position.
Fog Lamps
For vehicles with fog lamps, the
control is located next to the exterior
lamp control on the instrument
panel, to the left of the steering
column.
The ignition must be in the ON/RUN
position for the fog lamps to
come on.
#(Fog Lamps):Press to turn the
fog lamps on or off. A light will come
on in the instrument cluster.
When the fog lamps are turned on,
the parking lamps automatically
turn on.
When the headlamps are changed
to high beam, the fog lamps also go
off. When the high-beam headlamps
are turned off, the fog lamps will
come on again.
Some localities have laws that
require the headlamps to be on with
the fog lamps.
Auxiliary
Roof-Mounted Lamp
If the vehicle has this feature, this
button includes wiring provisions for
a dealer or a qualified service center
to install an auxiliary roof lamp.
This button is on the overhead
console.
When the wiring is connected to an
auxiliary roof-mounted lamp,
pressing the bottom of the button
will activate the lamp and illuminate
an indicator light at the bottom of
this button. Pressing the top of the
button will turn off the roof-mounted
lamp and indicator.

Black plate (64,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
9-64 Driving and Operating
A. Chassis harness connector
B. Release tab
4. Feed the wiring harness through the pickup box, then plug the
camera connectors together to
prevent contamination.
5. Remove the tailgate. See Tailgate on page 2‑9 for more
information.
6. Reinstall the license plate.
Reverse this procedure to reinstall
the RVC and make sure the
grommet and connection are
secure.
When the System Does Not
Seem To Work Properly
The RVC system might not work
properly or display a clear image if:
.The RVC is turned off. See
“Turning the RVC System On or
Off” earlier in this section.
.It is dark.
.The sun or the beam of
headlamps is shining directly
into the camera lens.
.Ice, snow, mud, or anything else
builds up on the camera lens.
Clean the lens, rinse it with
water, and wipe it with a soft
cloth.
.The back of the vehicle is in an
accident, the position and
mounting angle of the camera
can change or the camera can
be affected. Be sure to have the
camera and its position and
mounting angle checked at your
dealer. The RVC system display in the
rearview mirror may turn off or not
appear as expected due to one of
the following conditions. If this
occurs the left indicator light on the
mirror will flash.
.A slow flash may indicate a loss
of video signal, or no video
signal present during the reverse
cycle.
.A fast flash may indicate that the
display has been on for the
maximum allowable time during
a reverse cycle, or the display
has reached an Over
Temperature limit.
The fast flash conditions are
used to protect the video device
from high temperature
conditions. Once conditions
return to normal the device will
reset and the green indicator will
stop flashing.

Black plate (92,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
9-92 Driving and Operating
exceeds the maximum amperage
rating of 40 amperes for the
auxiliary battery provision.
Trailer Wiring Harness
The vehicle is equipped with one of
the following wiring harnesses for
towing a trailer or hauling a slide-in
camper.
Basic Trailer Wiring
All regular, extended cab and crew
cab pickups have a seven-wire
trailer towing harness.
For vehicles not equipped with
heavy duty trailering, the harness is
secured to the vehicle's frame
behind the spare tire mount. The
harness requires the installation of a
trailer connector, which is available
through your dealer.
If towing a light-duty trailer with a
standard four-way round pin
connector, an adapter is available
from your dealer.Heavy-DutyTrailer Wiring Harness
Package
For vehicles equipped with heavy
duty trailering, the harness
connector is mounted in the bumper.
The seven-wire harness contains
the following trailer circuits:
.Yellow: Left Stop/Turn Signal
.Dark Green: Right Stop/Turn
Signal
.Brown: Taillamps
.White: Ground
.Light Green: Back-up Lamps
.Red: Battery Feed*
.Dark Blue: Trailer Brake*
*The fuses for these two circuits are
installed in the underhood electrical
center, but the wires are not
connected. They should be
connected by your dealer or a
qualified service center. The fuse
and wire for the ITBC is factory
installed and connected if the
vehicle is equipped with an ITBC.
The fuse for the battery feed is not
required if the vehicle has an
auxiliary battery. If the vehicle does
not have an auxiliary battery, have
your dealer or authorized service
center install the required fuse.
If charging a remote (non-vehicle)
battery, press the Tow/Haul Mode
button, if equipped, located at the
end of the shift lever. This will boost
the vehicle system voltage and
properly charge the battery. If the
trailer is too light for Tow/Haul
Mode, or the vehicle is not equipped
with Tow/Haul, turn on the