2014 GMC SIERRA 1500 Air conditioner

Black plate (17,1)GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
5853626) - 2014 - 3rd crc - 8/15/13
Instruments and Controls 5-17
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 ifthe 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.
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

Black plate (21,1)GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
5853626) - 2014 - 3rd crc - 8/15/13
Instruments and Controls 5-21
If the word ON or the on symbol is
lit on the passenger airbag status
indicator, it means that the front
outboard 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 front
outboard 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
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
The charging system light comes on
briefly when the ignition is turned
on, but the engine is not running, as a check to show the light is working.
It should go out when the engine is
started.
If the light stays on, or comes on
while driving, there may be a
problem with the electrical charging
system. Have it checked by your
dealer. Driving while this light is on
could drain the battery.
When this light comes on, or is
flashing, the Driver Information
Center (DIC) also displays a
message.
See
Battery Voltage and Charging
Messages on page 5-35.
If a short distance must be driven
with the light on, be sure to turn off
all accessories, such as the radio
and air conditioner.

Black plate (4,1)GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
5853626) - 2014 - 3rd crc - 8/15/13
8-4 Climate Controls
-(Defog):This mode clears the
windows of fog or moisture. Air is
directed to the windshield, floor
outlets, and side window vents.
0(Defrost): Press to clear the
windshield of fog or frost more
quickly. Air is directed to the
windshield and the side window
vents. The system automatically
forces outside air into the vehicle
and the air conditioning compressor
will run, unless the outside
temperature is close to freezing.
Do not drive the vehicle until all the
windows are clear.
See Air Vents on page 8-8.
@(Recirculation): Press to turn
on recirculation. An indicator light
comes on. Air is recirculated to
quickly cool the inside of the
vehicle. It can also be used to help
reduce outside air and odors that
enter the vehicle.
A/C (Air Conditioning): Press to
turn the air conditioning system on
or off. An indicator light comes on to show that the air conditioning is
enabled. If the fan is turned off, the
air conditioner will not run. The A/C
light will stay on even if the outside
temperatures are below freezing.
Rear Window Defogger
K(Rear Window Defogger):
Press to turn the rear window
defogger on or off. An indicator light
on the button comes on to show that
the rear window defogger is on.
The rear window defogger only
works when the ignition is in ON/
RUN. The rear window defogger
stays on for approximately
10 minutes after the button is first
pressed. Each subsequent press,
the rear window defogger stays on
for five minutes. The defogger also
turns off if the ignition is turned to
ACC/ACCESSORY or LOCK/OFF.
{Caution
Using a razor blade or sharp
object to clear the inside rear
window can damage the rear
window defogger. Repairs would
not be covered by the vehicle
warranty. Do not clear the inside
rear window with sharp objects.

Black plate (7,1)GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
5853626) - 2014 - 3rd crc - 8/15/13
Climate Controls 8-7
0(Defrost):Press to clear the
windshield of fog or frost more
quickly. Air is directed to the
windshield and the side window
vents. The air conditioning
compressor also comes on, unless
the outside temperature is below
freezing.
Do not drive the vehicle until all
windows are clear.
See Air Vents on page 8-8.
A/C (Air Conditioning): Press to
turn the air conditioning system on
or off. An indicator light comes on to
show that the air conditioning is
enabled. If the fan is turned off, the
air conditioner will not run. The A/C
light will stay on even if the outside
temperatures are below freezing.
@(Recirculation): Press to turn
on recirculation. An indicator light
comes on. Air is recirculated to
quickly cool the inside of the
vehicle. It can also be used to help
reduce outside air and odors that enter the vehicle. The air
conditioning compressor also comes
on when this mode is activated.
Rear Window Defogger
The rear window defogger uses a
warming grid to remove fog from the
rear window.
K(Rear Window Defogger):
Press to turn the rear window
defogger on or off. An indicator light
on the button comes on to show that
the rear window defogger is on.
The rear window defogger only
works when the ignition is in ON/
RUN. The rear window defogger
stays on for approximately
10 minutes after the button is first
pressed. Each subsequent press,
the rear window defogger stays on
for five minutes. The defogger also
turns off if the ignition is turned to
ACC/ACCESSORY or LOCK/OFF.
{Caution
Using a razor blade or sharp
object to clear the inside rear
window can damage the rear
window defogger. Repairs would
not be covered by the vehicle
warranty. Do not clear the inside
rear window with sharp objects.
Heated Mirror: If equipped with
heated outside rearview mirrors, the
mirrors heat to help clear fog or frost
from the surface of the mirror when
the rear window defog button is
pressed. See Heated Mirrors on
page 2-16.