2009 GMC YUKON engine

2. Set the driver’s and passenger’s temperature.
To nd your comfort setting, start with a 74°F (23°C)
temperature setting and allow about 20 minutes
for the system to regulate. Use the driver’s or
passenger’s temperature buttons to adjust the
temperature setting as necessary. If a temperature
setting of 60°F (15°C) is chosen, the system
remains at the maximum cooling setting. If a
temperature setting of 90°F (32°C) is chosen, the
system remains at the maximum heat setting.
Choosing either maximum setting will not cause the
vehicle to heat or cool any faster.
Do not to cover the solar sensor located on the top of
the instrument panel near the windshield. This
sensor regulates air temperature based on sun load and
also turns on the headlamps. For more information on
the solar sensor, see “Sensors” later in this section.
To avoid blowing cold air in cold weather, the system will
delay turning on the fan until warm air is available.
The length of delay depends on the engine coolant
temperature. Pressing the fan switch will override this
delay and change the fan to a selected speed.Manual Operation
DC(Fan Control):Press these buttons to increase or
decrease the fan speed.
Pressing either fan button while in automatic control
places the fan under manual control. The fan setting
remains displayed and the AUTO light turns off. The air
delivery mode remains under automatic control.
HG(Air Delivery Mode Control):Press these buttons
to change the direction of the airow in the vehicle.
Repeatedly press either button until the desired mode
appears on the display. Pressing either mode button
while the system is off changes the air delivery mode
without turning the system on. Pressing either mode
button while in automatic control places the mode under
manual control.
The air delivery mode setting is displayed and the AUTO
light turns off. The fan remains under automatic control.
H(Vent):Air is directed to the instrument panel outlets.
)(Bi-Level):Air is divided between the instrument
panel and oor outlets. Some air is directed towards the
windshield and side window outlets.
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6(Floor):Air is directed to the oor outlets, with
some to the windshield, side window outlets, and second
row oor outlets. In this mode, the system automatically
selects outside air.
-(Defog):This mode clears the windows of fog or
moisture. Air is directed to the windshield, oor outlets,
and side window vents. In this mode, the system
turns off recirculation and runs the air conditioning
compressor unless the outside temperature is close to
freezing. The recirculation mode cannot be selected
while in the defog mode.
0(Defrost):This mode removes fog or frost from the
windshield more quickly. Air is directed to the windshield
and side window vents, with some directed to the oor
vents. In this mode, the system automatically forces
outside air into the vehicle and runs the air conditioning
compressor unless the outside temperature is close to
freezing. The recirculation mode cannot be selected while
in the defrost mode.
Do not drive the vehicle until all the windows are clear.
#(Air Conditioning):Press to turn the air conditioning
(A/C) compressor on and off. An indicator light comes
on to show that the air conditioning is on.
If this button is pressed when the air conditioning
compressor is unavailable, the indicator ashes
three times and then turns off. If the air conditioning
is on and the outside temperature drops below a
temperature which is too cool for air conditioning to be
effective, the air conditioning light turns off to show
that the air conditioning mode has been canceled.
On hot days, open the windows long enough to let hot
inside air escape. This helps to reduce the time it
takes for the vehicle to cool down. It also helps the
system to operate more efficiently.
The air conditioning system removes moisture from the
air, so a small amount of water might drip under the
vehicle while idling or after turning off the engine.
This is normal.
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@(Recirculation):Press to turn the recirculation
mode on or off. An indicator light comes on to show that
the recirculation is on.
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 also be turned off by turning
off the ignition.
REAR:For vehicles with the rear heat and air
conditioning controls. Press to turn the rear climate
control system on or off. SeeRear Air Conditioning and
Heating System and Electronic Climate Controls on
page 3-33.Rear Window Defogger
The rear window defogger uses a warming grid to
remove fog from the rear window.
<(Rear Window Defogger):Press to turn the rear
window defogger on or off. It automatically turns off
several minutes after it has been activated. The defogger
can also be turned off by turning off the engine. 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 2-50.
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Automatic Operation, If Equipped.
AUTO:Press the air delivery mode button until this
setting is selected to control the inside temperature, air
delivery, and fan speed. AUTO appears in the display
when automatic operation is active.
+/−(Increase/Decrease Temperature):Press
the+or−buttons to increase or decrease the cabin
temperature. The rear control temperature display will
show the temperature setting increasing or decreasing.
The display only indicates climate control functions when
the system is in rear independent mode.
Manual Operation
DC(Fan Control):Press these buttons on the rear
seat audio control panel to increase or decrease the
airow. Pressing the fan up button when the system is off
will turn the system on. The air delivery mode will remain
under automatic control.
+/−(Temperature Control):Press these buttons to
adjust the temperature of the air owing into the
passenger area. Press the + button for warmer air and
press the−button for cooler air.
N(Air Delivery Mode Control):Press the mode
button to change the direction of the airow in the
vehicle. Repeatedly press the button until the desired
mode appears on the display. Multiple presses will cycle
through the delivery selections.
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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Speedometer and Odometer
The speedometer shows the vehicle’s 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).
Trip Odometer
The trip odometer can show 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 trip odometer display, to toggle
between the trip odometer and the regular odometer.
Holding the reset button for approximately one second
while the trip odometer is displayed resets it.
To display the odometer reading with the ignition off,
press the reset button.
Tachometer
The tachometer displays the engine speed in revolutions
per minute (rpm).
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
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 1-90for 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.
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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.
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 1-81.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 3-64
for more information.
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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/retailer for service.
{CAUTION:
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 3-37
for more information, including important safety
information.
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. See
DIC Warnings and Messages on page 3-64for 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.
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Voltmeter Gage
When the engine is not
running, but the ignition is
on, this gage shows
the battery’s state of
charge in DC volts.
When the engine is running, the gage shows the
condition of the charging system. The charging system
regulates voltage based on the state of the battery
for improved fuel economy and battery life. The gage
may transition from a higher to lower or a lower to higher
reading, this is normal. Readings between the low
and high warning zones indicate the normal operating
range. The gage may also read low during the fuel
economy mode, this is normal.Readings in the low warning zone may occur when a
large number of electrical accessories are operating in
the vehicle and the engine is left at an idle 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 full power. If
there is a problem with the battery charging system, this
light will come on or the SERVICE BATTERY
CHARGING SYSTEM DIC message will display. See
DIC Warnings and Messages on page 3-64and
Charging System Light on page 3-39for more
information.
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.
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