2009 GMC SIERRA engine

This mode recirculates and helps to quickly cool the
air inside the vehicle. It can be used to help prevent
outside air and odors from entering the vehicle.
The recirculation mode cannot be used with oor,
defog, or defrost modes. If recirculation is selected
with one of those modes, the indicator light ashes
three times and then turns off. The air conditioning
compressor also comes on when this mode is activated.
While in recirculation mode the windows may fog when
the weather is cold and damp. To clear the fog,
select either the defog or defrost mode and increase
the fan speed.
The recirculation mode can be turned off by pressing
the outside air button, or by turning off the ignition.
;(Outside Air):Press to turn the outside air mode
on. An indicator light on the button comes on to show
that outside is on. When selected, air from outside
the vehicle circulates throughout the vehicle. The outside
air mode can be used with all modes, but it cannot be
used with the recirculation mode.
Rear Window Defogger
The rear window defogger uses a warming grid to
remove fog from the rear window.
<(Rear Window Defogger):For vehicles with
this feature, press to turn the defogger on or off.
It automatically turns off several minutes after it has
been activated. The defogger can also be turned off by
turning the engine off. Do not drive the vehicle until
all the windows are clear.
Notice:Do not use a razor blade or sharp object
to clear the inside rear window. Do not adhere
anything to the defogger grid lines in the rear glass.
These actions may damage the rear defogger.
Repairs would not be covered by your warranty.
Heated Mirrors:For vehicles 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. SeeOutside Power Mirrors
on page 2-59.
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Outlet Adjustment
Use the air outlets located in the center and on the side
of the instrument panel to direct the airow. Use the
thumbwheels near the air outlets to open or close off
the airow.
Operation Tips

Clear away any ice, snow, or leaves from air inlets
at the base of the windshield that could block the
ow of air into the vehicle.
Keep the path under the front seats clear of objects
to help circulate the air inside of the vehicle more
effectively.
Use of non-GM approved hood deectors can
adversely affect the performance of the system.
Check with your dealer/retailer before adding
equipment to the outside of the vehicle.
Warning Lights, Gages, and
Indicators
Warning lights and gages can signal that something is
wrong before it becomes serious enough to cause
an expensive repair or replacement. Paying attention to
the warning lights and gages could prevent injury.
Warning lights come on when there may be or is a
problem with one of the vehicle’s functions. Some
warning lights come on briey when the engine is started
to indicate they are working.
Gages can indicate when there may be or is a problem
with one of the vehicle’s functions. Often gages and
warning lights work together to indicate a problem with
the vehicle.
When one of the warning lights comes on and stays on
while driving, or when one of the gages shows there
may be a problem, check the section that explains
what to do. Follow this manual’s advice. Waiting to do
repairs can be costly and even dangerous.
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Instrument Panel Cluster
The instrument cluster is designed to show how the vehicle is running. It shows how fast the vehicle is going, about
how much fuel the vehicle has and many other things needed to drive safely and economically. For vehicles with
a DURAMAX
®Diesel engine, see the DURAMAX®Diesel manual for more information. United States Light Duty Premium version shown. Canada, Uplevel, Base, Heavy Duty Clusters similar.
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Speedometer and Odometer
The speedometer shows the vehicle speed in both
miles per hour (mph) and kilometers per hour (km/h).
The odometer shows how far the vehicle has been
driven, in either miles (used in the United States)
or kilometers (used in Canada).
Engine Hour Meter Display
The Driver Information Center (DIC) can also display
the number of hours the engine has run. To display the
engine hours, turn the ignition off, press and hold the
reset button for at least four seconds. The hour meter
displays for up to 30 seconds, or until the ignition is
turned on. SeeDIC Operation and Displays (With DIC
Buttons) on page 3-53orDIC Operation and Displays
(Without DIC Buttons) on page 3-59for more
information.
Trip Odometer
The trip odometer shows how far the vehicle has been
driven since the trip odometer was last set to zero.
Press the reset button, located on the instrument panel
cluster next to the voltmeter, to toggle between the
trip odometer and the regular odometer. Holding the
reset button for approximately one second while the trip
odometer is displayed will reset it.
To display the odometer reading with the ignition off,
press the reset button.
SeeDIC Operation and Displays (With DIC Buttons)
on page 3-53orDIC Operation and Displays (Without
DIC Buttons) on page 3-59for more information.
Tachometer
The tachometer displays the engine speed in revolutions
per minute (rpm). For a description of how Grade Braking
affects vehicle speed while the Tow/Haul Mode is
activated, see “Grade Braking (Allison Transmission
®)”
underTow/Haul Mode on page 2-34for more information.
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Safety Belt Reminders
Safety Belt Reminder Light
When the engine is started, a chime sounds for
several seconds to remind a driver to fasten the safety
belt, unless the driver safety belt is already buckled.
The safety belt light comes
on and stays on for
several seconds, then
ashes for several more.
This chime and light are repeated if the driver remains
unbuckled and the vehicle is in motion. If the driver’s
safety belt is already buckled, neither the chime nor the
light comes on.
Passenger Safety Belt Reminder Light
Several seconds after the engine is started, a chime
sounds for several seconds to remind the front
passenger to buckle their safety belt. This only occurs
if the passenger airbag is enabled. SeePassenger
Sensing System on page 1-84for more information.
The passenger safety belt light, located on the
instrument panel, comes on and stays on for
several seconds and then ashes for several more.
This chime and light are
repeated if the passenger
remains unbuckled and
the vehicle is in motion.
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.
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Airbag Readiness Light
The system checks the airbag’s electrical system for
possible malfunctions. If the light stays on it indicates
there is an electrical problem. The system check
includes the airbag sensor, 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 1-73.
The airbag readiness light
ashes for a few seconds
when the engine is started.
If the light does not come
on then, have it xed
immediately.{CAUTION:
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
inate in a crash, or they could even inate
without a crash. To help avoid injury, have the
vehicle serviced right away.
If there is a problem with the airbag system, an airbag
Driver Information Center (DIC) message can also come
on. SeeDIC Warnings and Messages on page 3-66
for more information.
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Charging System Light
This light comes on briey
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/retailer.
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. SeeDIC Warnings and Messages on page 3-66
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.
Voltmeter Gage
For vehicles with a
voltmeter gage, this gage
indicates the battery
voltage when the ignition
is turned on.
When the ignition is on, this gage indicates the
battery voltage.
When the engine is running, this gage shows the
condition of the charging system. The gage 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 3-41for more information. The voltmeter gage
may also read lower when in fuel economy mode.
This is normal.
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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.Brake System Warning Light
With the ignition on, the brake system warning light
comes on when the parking brake is set. If the vehicle is
driven with the parking brake engaged, a chime sounds
when the vehicle speed is greater than 5 mph (8 km/h).
The vehicle’s hydraulic brake system is divided into
two parts. If one part is not working, the other part can
still work and stop the vehicle. For good braking,
both parts need to be working well.
If the warning light comes on and a chime sounds there
could be a brake problem. Have the brake system
inspected right away.
This light can also come on due to low brake uid.
SeeBrakes on page 5-40for more information.
United States
Canada
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