2008 CADILLAC STS air condition

The mode switch can also be used to select the defog
mode. Information on defogging and defrosting can
be found later in this section.
yAz(Fan):Press this switch to increase or
decrease the fan speed. Pressing this switch cancels
automatic operation and allows the operator to manually
select the amount of airow. Press AUTO to return to
automatic 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,
seePassenger Compartment Air Filter on page 3-55
andScheduled Maintenance on page 6-4.
h(Recirculation):Press this button to control the
air source for the climate control system. If in AUTO
mode, press this button once to select recirculation.
This mode keeps outside air from coming in the vehicle
and recirculates the air in the vehicle. It can be used
to prevent outside air and odors from entering the
vehicle or to help cool the air inside the vehicle
more quickly.
Recirculation is not available in the defrost mode
and shuts off when defog mode is selected. Both of
these features are designed to limit fogging in the
vehicle. If recirculation is selected during defog mode,
it automatically turns off after 10 minutes to limit
problems with fogging.In some conditions, using recirculation for long periods
of time can cause the air inside the vehicle to become
too dry or stuffy. To prevent this from happening,
after the air in the vehicle has cooled, select AUTO to
return to automatic climate control operation or push
the recirculation button again to select outside air.
Press this button a second time to select outside air.
:(Outside Air):This mode forces the system to
pull air from outside the vehicle. It can be used to bring
fresh air into the vehicle.
Air Quality Sensor:Your vehicle could have an air
quality sensor to help limit the climate control system
from pulling in some harmful exhaust fumes from older,
poorly running, or diesel-equipped vehicles that are
driving near you. This sensor, when active, monitors the
air quality in front of your vehicle and switches to air
recirculation when poor quality air is detected outside
your vehicle. Press the AUTO button on the climate
control to activate the air quality sensor. The word AUTO
comes on the center of the climate control display.
While the air quality sensor senses poor quality air,
the recirculation graphic displays.
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Under some conditions, the air quality sensor system
does not operate. In cold weather, the system might
not be active (even if AUTO is displayed) because
of concerns of fogging your windows, which may occur
by activating recirculation mode. Also, the air quality
sensor system does not remain in recirculation mode
for extended periods of time that could cause stuffy
or very dry conditions in the vehicle. Following a poorly
running vehicle for an extended period of time may
not keep recirculation active indenitely.
The air quality sensor does not activate due to organic
odors, like skunk, and may not activate on many
chemical-related odors. If you wish to limit these types
of odors, manually select recirculation. Your vehicle
could also have a charcoal lter that can limit many
odors from being pulled into your vehicle. This
lter needs to be changed periodically. SeeScheduled
Maintenance on page 6-4. The air quality sensor
system does not protect against carbon monoxide (CO),
which you cannot see or smell. SeeEngine Exhaust
on page 2-38.
O(Power Driver’s Temperature):Press the power
button located on the driver’s side of the climate
control panel to turn the entire climate control system
on or off. Turn the knob to increase or decrease
the temperature inside the vehicle.
O(Power Passenger’s Temperature):Press the
power button located on the passenger’s side of
the climate control panel to turn the passenger’s climate
control system on if they wish to have a different
setting than the driver. Turn the knob to increase or
decrease the temperature for the front passenger.
Turning the passenger’s side power button off will not
shut off the climate control system for the passenger.
The system is set to the same setting as the driver.
{(Ventilated Seat):Press this button, to turn
on the driver or passenger’s side ventilated seat,
if the vehicle has this feature. SeeHeated and
Ventilated Seats on page 1-3.
J(Heated Seat):Press this button, to turn on the
driver or passenger’s side heated seat and seatback,
if the vehicle has this feature. SeeHeated and
Ventilated Seats on page 1-3.
^(Air Conditioning):Press this button to manually
turn off the air conditioning compressor. Press AUTO
to return to automatic operation. To limit fogging on
the windshield, the air conditioning compressor
cannot be off while in the defrost mode.
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Sensors
There is a solar sensor located on the instrument panel,
near the windshield.
There is also an interior temperature sensor located
next to the steering wheel on the instrument panel.
These sensors monitor the solar radiation and the air
inside the vehicle, then use the information to adjust
the temperature, the fan speed and the air delivery
system, in order to maintain the selected temperature.The system may also supply cooler air to the side of the
vehicle facing the sun. Do not cover the sensors or the
automatic climate control system will not work properly.
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 the windshield. Use the defog mode to clear the
windows of fog or moisture and warm the passengers.
Use the defrost mode to remove fog or frost from
the windshield more quickly.
yNz(Mode):Press this button until defog appears
on the display.
-(Defog):This mode directs the air between the
windshield and oor outlets with some air supplied to
the outboard panel outlets and side window defogging
outlets. 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 is cancelled when the system
enters the defog mode. If recirculation is selected while
in the defog mode, it is cancelled after 10 minutes.
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If there is fogging on the side windows, remain in
defog or defrost mode until they clear.
0(Defrost):Press this button to direct most of the
air to the windshield, with some air directed to the
side windows and outboard panel 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.
This mode can also cause the fan speed and air
temperature to increase.
Rear Window Defogger
The rear window defogger uses a warming grid to
remove fog or frost from the rear window.
The rear window defogger only works when the
ignition is on or during remote start, if programmed.
See “Personal Settings Menu” underVehicle
Personalization on page 2-60for additional information.
=(Rear Window Defogger):Press this button to
turn the rear window defogger on or off. Be sure to
clear as much snow from the rear window as possible.
The rear window defogger turns off about 10 minutes
after the button is pressed. If the vehicle’s speed
is above 30 mph (48 km/h), the rear defogger stays
on continuously. If turned on again, the defogger
only runs for about ve minutes before turning off.
The defogger can also be turned off by pressing the
button again or by turning off the engine.
The heated outside rearview mirrors also heat to help
clear fog or frost from the surface of the mirror when
the rear window defogger is on. SeeOutside Power
Heated Mirrors on page 2-43.
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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The right knob controls the air delivery to the rear
passengers. Turning the knob all the way to the left will
shut off airow to the rear passengers. Operating with
the rear air delivery off may make the entire vehicle
warm or cool less quickly. It may also increase the air
rush sound of the front system.
9(Off):This is the off position.
Y(Vent):This mode directs all the rear passenger
airow to the outlets in the console. This is the
normal position for cool down conditions.
\(Bi-Level):This mode directs airow to the
console outlets and the oor.
[(Floor):This mode directs all of the airow to the
oor. This is the normal position for warm up conditions.
The amount of airow to the rear passengers is
controlled automatically by the front climate control
system, regardless of optional equipment. Airow to
the rear system will be turned off when defrost is
selected on the front climate control panel to direct
air to clear the windshield.
Vehicles equipped with a rear climate control panel,
also, have heated rear seats. There are two buttons,
each with three indicator lights, located between thetwo climate control knobs on the rear climate control
panel, to control the rear heated seats. SeeHeated
Seats on page 1-7for additional information.
Be sure to keep the area under the front seats clear
of any objects so the air in your vehicle can circulate
effectively.
Passenger Compartment Air Filter
Your vehicle may be equipped with a passenger
compartment air lter. There are two types of lters
available. There is a standard dust lter that traps small
particles including pollen. There is, also, a dust/odor
lter available that traps dust and pollen and also uses
a charcoal element to help reduce many offensive
odors from entering your vehicle. The lter will need
to be changed periodically. For information on how
often to change the passenger compartment air lter,
seeScheduled Maintenance on page 6-4.
Notice:Driving without a passenger compartment
air lter in place can cause water and small particles,
like paper and leaves, to be pulled into your climate
control system which may cause damage to it. Make
sure you always replace the old lter with a new one.
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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 in the instrument
panel cluster ever comes on and stays on,
it means that something may be wrong with
the airbag system. If this ever happens,
have the vehicle serviced promptly, because
an adult-size person sitting in the right front
passenger’s seat may not have the protection
of the airbag(s). SeeAirbag Readiness Light
on page 3-60for more on this, including
important safety information.
Charging System Light
This light will come
on briey when you
turn on the ignition,
but the engine is not
running, as a check to
show you it is working.
It should go out once the engine is running. If it stays
on, or comes on while you are driving, you may have
a problem with the charging system. A charging system
Driver Information Center (DIC) message may also
appear. SeeDIC Warnings and Messages on page 3-80
for more information. This light could indicate that
you have problems with a generator drive belt,
or another electrical problem. Have it checked right
away. If you must drive a short distance with the
light on, be certain to turn off all your accessories,
such as the radio and air conditioner.
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Malfunction Indicator Lamp
Check Engine Light
A computer system called OBD II (On-Board
Diagnostics-Second Generation) monitors operation of
the fuel, ignition, and emission control systems. It makes
sure that emissions are at acceptable levels for the life of
the vehicle, helping to produce a cleaner environment.
The check engine light
comes on to indicate
that there is an OBD II
problem and service
is required.
Malfunctions often are indicated by the system before
any problem is apparent. This can prevent more serious
damage to your vehicle. This system is also designed
to assist your service technician in correctly diagnosing
any malfunction.
Notice:If you keep driving your vehicle with this
light on, after a while, the emission controls
might not work as well, your vehicle’s fuel economy
might not be as good, and the engine might not
run as smoothly. This could lead to costly repairs
that might not be covered by your warranty.Notice:Modications made to the engine,
transmission, exhaust, intake, or fuel system of
your vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect your vehicle’s emission
controls and can cause this light to come on.
Modications to these systems could lead to costly
repairs not covered by your warranty. This could
also result in a failure to pass a required Emission
Inspection/Maintenance test. SeeAccessories
and Modifications on page 5-3.
This light comes on briey, as a check to show it is
working, as you start the engine. If the light does not
come on, have it repaired. This light also comes
on during a malfunction in one of two ways:
Light Flashing— A misre condition has been
detected. A misre increases vehicle emissions
and could damage the emission control system
on your vehicle. Diagnosis and service might
be required.
Light On Steady— An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service might be required.
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ENGINE COOLANT HOT IDLE ENGINE
Notice:If you drive your vehicle while the engine
is overheating, severe engine damage may occur.
If an overheat warning appears on the instrument
panel cluster and/or DIC, stop the vehicle as soon
as possible. Do not increase the engine speed
above normal idling speed. SeeEngine Overheating
on page 5-29for more information.
This symbol appears
with this message.
This message displays when the engine coolant
temperature is too hot. Stop and allow the vehicle
to idle until it cools down. SeeEngine Coolant
Temperature Warning Light on page 3-66.
SeeOverheated Engine Protection Operating Mode
on page 5-31for information on driving to a safe
place in an emergency.
ENGINE HOT – AC
(Air Conditioning) OFF
This message displays when the engine coolant
becomes hotter than the normal operating temperature.
SeeEngine Coolant Temperature Gage on page 3-67.
To avoid added strain on a hot engine, the air
conditioning compressor is automatically turned off.
When the coolant temperature returns to normal,
the air conditioning compressor turns back on.
You can continue to drive your vehicle.
If this message continues to appear, have the system
repaired by your dealer/retailer as soon as possible
to avoid damage to the engine.
ENGINE OVERHEATED STOP ENGINE
Notice:If you drive your vehicle while the engine
is overheating, severe engine damage may occur.
If an overheat warning appears on the instrument
panel cluster and/or DIC, stop the vehicle as soon
as possible. SeeEngine Overheating on page 5-29
for more information.
This message displays when the engine has overheated.
Immediately look for a safe place to pull your vehicle
over and turn the engine off right away to avoid severe
engine damage. SeeEngine Overheating on page 5-29
andOverheated Engine Protection Operating Mode
on page 5-31. A chime also sounds when this message
is displayed.
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