2009 GMC YUKON ECO mode

Driver and Passenger Side Temperature
Control
The driver and passenger side temperature buttons are
used to adjust the temperature of the air coming through
the system on the driver or passenger’s side of the
vehicle. The temperature can be adjusted even if the
system is turned off. This is possible since outside air
always ows through the system as the vehicle is moving
forward unless it is set to recirculation mode. See
“Recirculation” later in this section.
Press the + or−buttons to increase or decrease the
cabin temperature. The driver side or passenger
side temperature display shows the temperature setting
decreasing or increasing.
The passenger’s temperature setting can be set to
match the driver’s temperature setting by pressing the
PASS button and turning off the PASS indicator.
When the passenger’s temperature setting is set
different than the driver’s setting, the indicator on the
PASS button illuminates and both the driver side
and passenger side temperature displays are shown.
Automatic Operation
AUTO (Automatic):When automatic operation is
active the system will control the inside temperature, the
air delivery, and the fan speed.
Use the steps below to place the entire system in
automatic mode:
1. Press the AUTO button.
When AUTO is selected, the display will change to
show the current temperature(s) and AUTO will
be lit on the display. The current delivery mode and
fan speed will also be displayed for approximately
5 seconds.
When AUTO is selected, the air conditioning
operation and air inlet will be automatically
controlled. The air conditioning compressor will run
when the outside temperature is over about
40°F (4°C). The air inlet will normally be set to
outside air. If it is hot outside, the air inlet may
automatically switch to recirculate inside air to help
quickly cool down the vehicle. The light on the
button comes on in recirculation.
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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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Sensors
The solar sensor, located in the defrost grille in the
middle of the instrument panel, monitors the solar heat.
Do not cover the solar sensor or the system will not
work properly.The interior temperature sensors located in the headliner
above the driver side seat and if equipped, in the
headliner above the second row seats measure the
temperature of the air inside the vehicle.
There is also an exterior temperature sensor located
behind the front grille. This sensor reads the outside air
temperature and helps maintain the temperature inside
the vehicle. Any cover on the front of the vehicle could
cause a false reading in the displayed temperature.
The climate control system uses the information from
these sensors to maintain your comfort setting by
adjusting the outlet temperature, fan speed, and the air
delivery mode. The system may also supply cooler
air to the side of the vehicle facing the sun. The
recirculation mode will also be used as needed to
maintain cool outlet temperatures.
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REAR:Press the REAR button on the front climate
control system to turn the rear climate control system on
or off. An indicator comes on when the rear system is on.
SeeClimate Control System on page 3-22orDual
Automatic Climate Control System on page 3-25. The
rear system can also be turned off by turning the rear fan
knob to the
9position.
Mimic Mode:This mode matches the rear climate
control to the front climate control airow settings.
It comes on when REAR is pressed the rst time.
Independent Mode:This mode directs rear seating
airow according to the settings of the rear controls.
It comes on when any rear control is adjusted.
Temperature Control:Turn clockwise or
counterclockwise to increase or decrease the airow
temperature into the passenger area.Fan Control:Turn clockwise or counterclockwise to
increase or decrease the fan speed.
Air Delivery Mode Control:Turn clockwise or
counterclockwise to change the direction of the airow.H(Vent):Air is directed through the headliner
outlets.
)(Bi-Level):Air is directed through the oor and
headliner outlets. The rear system oor outlets are
located directly behind the second row seats. The ow
can be divided between vent and oor outlets depending
upon where the knob is placed between the settings.
6(Floor):Air is directed to the oor outlets. The rear
system oor outlets are located directly behind the
second row seats.
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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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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 Two-mode Hybrid, see the Two-mode Hybrid manual for more information.United States 4-Speed version shown. 6-Speed and Canada similar.
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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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Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but readings above
the low pressure zone indicate the normal operating
range. When the oil pressure reaches the low
pressure zone, the OIL PRESSURE LOW STOP
ENGINE message appears in the Driver Information
Center (DIC). SeeDIC Warnings and Messages
on page 3-64andEngine Oil on page 5-15for more
information.
A reading in the low pressure zone may be caused by
a dangerously low oil level or some other problem
causing low oil pressure. Check the oil as soon
as possible.
{CAUTION:
Do not keep driving if the oil pressure is low. The
engine can become so hot that it catches re.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.
Notice:Lack of proper engine oil maintenance can
damage the engine. The repairs would not be
covered by the vehicle warranty. Always follow the
maintenance schedule in this manual for changing
engine oil.
If the vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
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