climate control GMC YUKON 2009 User Guide

Electric Power Management
The vehicle has Electric Power Management (EPM) that
estimates the battery’s temperature and state of charge.
It then adjusts the voltage for best performance and
extended life of the battery.
When the battery’s state of charge is low, the voltage is
raised slightly to quickly bring the charge back up. When
the state of charge is high, the voltage is lowered slightly
to prevent overcharging. If the vehicle has a voltmeter
gage or a voltage display on the Driver Information
Center (DIC), you may see the voltage move up or down.
This is normal. If there is a problem, an alert will be
displayed.
The battery can be discharged at idle if the electrical
loads are very high. This is true for all vehicles. This is
because the generator (alternator) may not be spinning
fast enough at idle to produce all the power that is
needed for very high electrical loads.
A high electrical load occurs when several of the
following are on, such as: headlamps, high beams, fog
lamps, rear window defogger, climate control fan at
high speed, heated seats, engine cooling fans, trailer
loads, and loads plugged into accessory power outlets.
EPM works to prevent excessive discharge of the
battery. It does this by balancing the generator’s output
and the vehicle’s electrical needs. It can increaseengine idle speed to generate more power, whenever
needed. It can temporarily reduce the power demands of
some accessories.
Normally, these actions occur in steps or levels, without
being noticeable. In rare cases at the highest levels of
corrective action, this action may be noticeable to the
driver. If so, a Driver Information Center (DIC) message
might be displayed, such as BATTERY SAVER ACTIVE,
BATTERY VOLTAGE LOW, or LOW BATTERY. If this
message is displayed, it is recommended that the driver
reduce the electrical loads as much as possible. SeeDIC
Warnings and Messages on page 3-64.
Battery Run-Down Protection
This feature shuts off the dome, and reading lamps
if they are left on for more than 10 minutes when
the ignition is off. This will keep the battery from
running down.
Accessory Power Outlet(s)
Accessory power outlets can be used to connect
auxiliary electrical equipment, such as a cellular
telephone.
There are two under the climate controls, one inside
the center oor console, one on the rear of the center
oor console and one accessory power outlet in the
rear cargo area on the passenger side.
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Climate Controls
Climate Control System
The heating, cooling, and ventilation in the vehicle can
be controlled with this system.
A. Fan Control
B. REAR
C. Recirculation
D. Air Delivery
Mode Control
E. Air ConditioningF. Driver and
Passenger
Temperature
Controls
G. Rear Window
DefoggerTemperature Control:Move the thumbwheels up or
down to increase or decrease the temperature on
the driver’s side or the passenger side of the vehicle for
the dual zone system.9(Fan Control):Turn the left knob clockwise or
counterclockwise to increase or decrease the fan speed.
Turn the knob all the way counterclockwise to turn the
front system off.
Air Delivery Mode Control:Turn clockwise or
counterclockwise to change the airow direction inside
the vehicle. By positioning the knob between two modes,
a combination of those modes is selected.
Select from the following modes:
H(Vent):Air is directed to the instrument panel
outlets.
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h(Recirculation):Press this button to turn the
recirculation mode on or off. An indicator light comes on
to show that 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, defrost,
or defogging modes. If recirculation is selected while in
one of those modes, the indicator ashes three times and
turns off. The air conditioning compressor will also come
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 engine.
REAR:Press to turn the rear heating and air
conditioning on. SeeRear Air Conditioning and Heating
System on page 3-31orRear Air Conditioning and
Heating System and Electronic Climate Controls
on page 3-33for more information.Rear Window Defogger
The rear window defogger uses a warming grid to
remove fog from the rear window.
<(Rear Window Defogger):Press this button to
turn the rear window defogger on or off. The system
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.
For vehicles with heated outside rearview mirrors, the
mirrors will heat to help clear fog or frost from the
surface of the mirror when the rear window defog button
is pressed.
Notice:Do not use anything sharp on the inside of
the rear window. If you do, you could cut or damage
the warming grid, and the repairs would not be
covered by the vehicle warranty. Do not attach a
temporary vehicle license, tape, a decal or anything
similar to the defogger grid.
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Dual Automatic Climate Control
System
The heating, cooling, and ventilation in the vehicle can
be controlled with this system. The vehicle also has
a ow-through ventilation system described later in this
section.
If this vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
A. Fan Control
B. AUTO
C. Defrost
D. Recirculation
E. REARF. Air Delivery
Mode Control
G. Driver Temperature
ControlH. Display
I. Power Button
J. Rear Window
DefoggerK. Air Conditioning
L. PASS
M. Passenger
Temperature Control
O(On/Off):Press to turn the climate control system on
or off. Outside air still enters the vehicle, and is
directed to the oor. This direction can be changed by
pressing the mode button. Recirculation can be selected
once you have selected vent or bi-level mode. The
temperature can also be adjusted using either
temperature button. If the air delivery mode or
temperature settings are adjusted with the system off,
the display illuminates briey to show the settings
and then returns to off. The system can be turned back
on by pressing either
O,D,C,#, the defrost or
the AUTO button.
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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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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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Rear Air Conditioning and Heating
System and Electronic Climate
Controls
For vehicles with the rear heat and air conditioning
controls, they are integrated with the rear seat audio
controls located in the center console. The system can be
controlled from the front controls as well as the rear
controls.
A. Fan Control
B. Air Delivery Mode Control
C. Temperature ControlREAR: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.
The rear climate control system can also be turned off by
pressing and holding theCbutton. To turn the system on
from the rear seats, press any rear climate control button,
except the
Cbutton.
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.
To turn the system on from the rear, press any
rear climate control button, except the
Cbutton.
Rear Climate Control with Rear Seat Audio Controls
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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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4. Press the trip/fuel button until the vehicle heading,
for example, N for North, is displayed in the DIC.
Or, if the vehicle does not have DIC buttons, press
and hold the trip odometer reset stem for two
seconds to select the next available variance zone.
Repeat this step until the appropriate variance
zone is displayed.
5. If calibration is necessary, calibrate the compass.
See “Compass Calibration Procedure” following.
Compass Calibration
The compass can be manually calibrated. Only calibrate
the compass in a magnetically clean and safe location,
such as an open parking lot, where driving the vehicle in
circles is not a danger. It is suggested to calibrate
away from tall buildings, utility wires, manhole covers, or
other industrial structures, if possible.
If CAL should ever appear in the DIC display, the
compass should be calibrated.
If the DIC display does not show a heading, for example,
N for North, or the heading does not change after
making turns, there may be a strong magnetic eld
interfering with the compass. Such interference may be
caused by a magnetic CB or cell phone antenna
mount, a magnetic emergency light, magnetic note pad
holder, or any other magnetic item. Turn off the
vehicle, move the magnetic item, then turn on the
vehicle and calibrate the compass.To calibrate the compass, use the following procedure:
Compass Calibration Procedure
1. Before calibrating the compass, make sure the
compass zone is set to the variance zone in
which the vehicle is located. See “Compass
Variance (Zone) Procedure” earlier in this section.
Do not operate any switches such as window,
sunroof, climate controls, seats, etc. during
the calibration procedure.
2. Press the vehicle information button until PRESS
V
TO CALIBRATE COMPAS (Compass) displays. Or,
if the vehicle does not have DIC buttons, press
the trip odometer reset stem until CALIBRATE
COMPASS displays.
3. Press the set/reset button to start the compass
calibration. Or, if the vehicle does not have DIC
buttons, press and hold the trip odometer reset stem
for two seconds to start the compass calibration.
4. The DIC will display CALIBRATING: DRIVE IN
CIRCLES. Drive the vehicle in tight circles at less
than 5 mph (8 km/h) to complete the calibration. The
DIC will display CALIBRATION COMPLETE for a
few seconds when the calibration is complete. The
DIC display will then return to the previous menu.
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