2008 BUICK LUCERNE Owner's Manual

#(Air Conditioning):Press this button to turn the
air conditioning system on or off. When this button
is pressed, an indicator light below the button comes on
to show that this mode is activated. Air conditioning
can be selected in any mode as long as the fan knob is
not in the off position.
On hot days during the vehicle’s initial start-up, open
the windows to let hot inside air escape; then close
them. This helps to reduce the time it takes for
the vehicle to cool down. It also helps the system to
operate more efficiently.
For quicker cool down on hot days, do the following:
1. Select the vent air mode.
2. Select the recirculation mode.
3. Select the air conditioner.
4. Select the coolest temperature.
5. Select the highest fan speed.
The air-conditioning system removes moisture from the
air, so a small amount of water may drip underneath
the vehicle while idling or after turning off the engine.
This is normal.Defogging and Defrosting
Fog on the inside of the vehicle is a result of high
humidity causing moisture to condense on the cool
window glass. This can be minimized if the climate
control system is used properly. There are two modes
to clear frost or fog from the windshield. Use the
oor/defog mode to clear the windows of condensation
and to warm the vehicle’s occupants. Use the defrost
mode to remove frost or condensation from the
windshield quickly.
See “Rear Window Defogger” later in this section for
information on clearing the rear window of fog or ice.
Turn the right knob to select the defog or defrost mode.
The recirculation mode cannot be selected while in
these modes.
-(Floor/Defog):This mode directs half of the air to
the windshield and the side window outlets and half
to the oor outlets. The system runs the air conditioning
compressor unless the outside temperature is near or
below freezing.
0(Defrost):This mode directs most of the air to the
windshield and the side window outlets. The system
runs the air conditioning compressor unless the outside
temperature is near or below freezing.
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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. An indicator
light below the button comes on to show that the rear
window defogger is activated. Be sure to clear as much
snow from the rear window as possible.
The rear window defogger will only work when the ignition
is in ON/RUN. The rear window defogger stays on for
about 20 minutes after the button is pressed if traveling at
slow speeds. At higher vehicle speeds, the rear defogger
may stay on continuously. If turned on again, the
defogger only runs for about 10 minutes before turning
off. The defogger can be turned off by pressing the button
again, by turning the ignition to ACC/ACCESSORY or
ON/RUN, or by turning off the engine.
If your vehicle has heated outside rearview mirrors, the
mirrors heat to help clear fog or frost from the surface of
the mirror when the rear window defogger is on. See
Outside Automatic Dimming Heated Mirror on page 2-38
for more information.
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 your warranty. Do not attach a
temporary vehicle license, tape, a decal or anything
similar to the defogger grid.
Dual Automatic Climate Control
System
The heating, cooling, and ventilation for the vehicle can
be controlled with this system.
If your vehicle has the remote start feature and it is
activated, the climate control system heats or cools the
inside of the vehicle, with the settings used before
the vehicle was turned off. The heated seats, if
the vehicle has them, and the rear window defogger will
be turned on by the climate control system when it is
cold outside. The cooled seat setting is not activated
during a remote start. Normal operation of the system
will return after the key is turned to the ON/RUN
position. SeeRemote Keyless Entry (RKE) System
Operation on page 2-5for more information.
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Automatic Operation
AUTO (Automatic Fan):When AUTO is selected on
the fan control, the system automatically adjusts the fan
speed. If the OnStar
®system is activated when this
position is selected, the fan speed will lower.
AUTO (Automatic Mode)
1. Turn the fan control to AUTO.
2. Turn the mode control to AUTO.
3. Adjust the temperature to a comfortable setting
between 68°F (21°C) and 78°F (26°C).
Choosing the coldest or warmest temperature
setting will not cause the system to heat or cool any
faster. In cold weather, the system starts at
reduced fan speeds to avoid blowing cold air into
the vehicle until warmer air is available. The system
will start out blowing air to the oor, but may
change modes automatically as the vehicle warms
up to maintain the chosen temperature setting.
The length of time needed to warm the interior
depends on the outside temperature.
4. Wait a few minutes for the system to automatically
regulate. Then adjust the temperature as necessary
to nd your comfort setting.
Do not cover the solar sensor located in the center of
the instrument panel, near the windshield. For more
information on the solar sensor, see “Sensors” later in
this section.After the vehicle is started, the display shows the
interior temperature settings.
When the ENG/MET (English/metric) button on the
Driver Information Center (DIC) is pressed, the display
shows readings in Fahrenheit or Celsius. Use the
ENG/MET button to toggle between the readings.
AUTO (Automatic Air Conditioning):If AUTO is
selected on the fan or mode control, the system
automatically controls the air conditioning compressor.
The A/C compressor runs automatically even at cool
outside temperatures in order to dehumidify the air. The
A/C indicator light is lit when the system is operating
automatically. Press the A/C button on the fan control to
turn off the A/C. To clear windows better in defog or
defrost modes, the A/C compressor runs automatically
in damp cool conditions.
h(Auto Recirculation):If AUTO is selected on
either the fan or mode control, the system automatically
controls the supply of fresh outside air or recirculates
the interior air to cool the car faster. The indicator
light on the recirculation button will light whenever the
system switches to recirculation. You may force outside
air by pressing the outside air button. The next time
AUTO fan or mode is selected, it will reset back
to AUTO operation.
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Manual Operation
9(Fan):Turn the left knob either to the left or right to
adjust the fan speed. Turning this control completely
counterclockwise turns on the automatic fan operation.
If the airow seems low when the fan speed is at
the highest setting, the passenger compartment air lter
may need to be replaced. For more information, see
Passenger Compartment Air Filter on page 3-30
andScheduled Maintenance on page 6-4.
9(Off):Turn the left control to this position to turn
the climate control system off. Outside air still enters the
vehicle and is directed to the oor. The airow direction
and temperature can be adjusted, as indicated below.
If the temperature is adjusted while the system is off, the
display will light to show the current settings.
Mode Control:Turn the right knob clockwise or
counterclockwise to change the airow direction.
F(Vent):This mode directs outside air to the
instrument panel outlets.
*(Bi-Level):This mode splits the air between the
instrument panel outlets and the oor outlets. In
automatic operation, cooler air is directed to the upper
outlets and warmer air to the oor outlets.
7(Floor):This mode automatically uses outside air
and directs most to the oor outlets. Some air is directed
toward the side window outlets and to the windshield.
If recirculation is selected while in this mode, it stays on
for three minutes to reduce windshield fogging.
The mode control can also be used to select the
oor/defog mode. Information on defogging and
defrosting can be found later in this section.
#(Air Conditioning):Press the center of the left
control knob to override the automatic system and turn
the air conditioning system on or off. When this
button is pressed, an indicator light below the button
comes on to show that this mode is activated.
The air conditioning system removes moisture from the
air, so a small amount of water might drip underneath
the vehicle while idling or after turning off the engine.
This is normal.
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:(Outside Air):This mode lets outside air enter
the vehicle. When the button is pressed, an indicator
light turns on. Pressing the recirculation button cancels
this mode.
?(Recirculation):Press this button to recirculate
cabin air through the vehicle. An indicator light below the
button comes on to show that this mode is activated.
This mode can be used to prevent outside air and odors
from entering the vehicle or to help cool the air inside
the vehicle more quickly. This mode cannot be selected
while in the defog or defrost modes. If you try to
select the recirculation mode, the indicator light ashes
three times and turns off.
Operation in this mode during periods of high humidity
and cool outside temperatures may result in increased
window fogging. If window fogging is experienced, select
the defrost mode.
wx(Driver Temperature Controls):Press these
buttons next to the fan control to manually increase or
decrease the temperature inside the vehicle.
wx(Passenger Temperature Controls):Press
these buttons next to the mode control to manually
increase or decrease the temperature for the front
passenger. If the passenger climate control system is
off, pressing one of these buttons turns it on.
PASS (Passenger Climate Control):Press this button
to turn the passenger climate control systems on or off.
When the passenger climate control system is on, the
passenger temperature setting is displayed.
If the PASS button is pressed to turn the passenger
temperature setting off, the driver temperature setting
controls the temperature for the entire vehicle.
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Sensors
The solar sensor, located in the defrost grille, in the
middle of the instrument panel, monitors the solar
radiation. Do not cover the solar sensor or the system
will not work properly.
There is also an interior temperature sensor located
next to the steering wheel that measures 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 temperature reading to display.
In order to prevent false temperature readings at startup,
the displayed temperature will not change until the
following occurs:
Vehicle speed is above 10 mph (16 km/h) for
ve minutes.
Vehicle speed is above 32 mph (51 km/h) for
two and a half minutes.
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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Defogging and Defrosting
Fog on the inside of windows is a result of high humidity
(moisture) condensing on the cool window glass. This
can be minimized if the climate control system is
used properly. There are two modes to clear fog from
your windshield, defog and defrost.
W(Floor/Defog):Use this mode to clear the windows
of fog or moisture and to warm the passengers.
Turning the control to this mode directs about half of the
air to the oor outlets and the remaining air is directed
to the side window outlets and to the windshield.
When this mode is selected, the system turns off
recirculation and runs the air-conditioning compressor
unless the outside temperature is at or below freezing.
The recirculation mode cannot be selected while in
the oor/defog mode.
0(Defrost):Use this mode to remove fog or frost
from the windshield more quickly. Turning the control to
this mode directs most of the air to the windshield
and the side window outlets. In this mode, the system
automatically turns off recirculation and runs the
air-conditioning compressor, unless the outside
temperature is at or below freezing. Recirculation cannot
be selected while in the defrost mode.
Rear Window Defogger
The rear window defogger uses a warming grid to
remove fog or frost from the rear window.
<(Rear Defogger):Press this button to turn the rear
window defogger on or off. An indicator light below
the button comes on to show that the rear window
defogger is activated. Be sure to clear as much snow
from the rear window as possible.
The rear window defogger will only work when the
ignition is in ON/RUN. The rear window defogger stays
on for about 20 minutes after the button is pressed if
you are traveling at slower vehicle speeds. At higher
vehicle speeds the rear window defogger may stay on
continuously. If turned on again, the defogger only
runs for about 10 minutes before turning off. The
defogger can be turned off by pressing the button again,
by turning the ignition to ACC/ACCESSORY or
ON/RUN, or by turning off the engine.
The heated outside rearview mirrors will heat to help
clear fog or frost from the surface of the mirror when the
rear window defogger is on. SeeOutside Automatic
Dimming Heated Mirror on page 2-38for more
information.
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.
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Outlet Adjustment
Use the levers, located in the middle of the front outlets,
to change the direction of the airow. Use the
thumbwheel located between the outlets to turn them on
and off.
If your vehicle has rear seat outlets, adjust the direction of
the airow using the lever in the center of each outlet.
Operation Tips

Clear away any ice, snow, or leaves from the air
inlets at the base of the windshield that could
block the ow of air into your vehicle.
Use of non-GM approved hood deectors can
adversely affect the performance of the system.
Keep the path under the front seats clear of objects
to help circulate the air inside the vehicle better.
Passenger Compartment Air Filter
Outside air is routed through a passenger compartment
air lter before entering the vehicle. This lter removes
certain particles from the air, including pollen and
dust particles. The lter should be replaced as part of
routine scheduled maintenance. SeeScheduled
Maintenance on page 6-4for when to replace the lter.
The access panel for the passenger compartment air
lter is located under the hood near the windshield,
on the passenger’s side of the vehicle.
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