2008 CADILLAC DTS air condition

Automatic Operation
AUTO9(Automatic Fan):When this position is
selected on the fan control, the system adjusts the fan
speed. If the OnStar
®system is activated when this
position is selected, the climate control fan speed
will lower.
AUTO (Automatic Mode):
1. Turn the fan control to the AUTO position.
2. Turn the mode control to the AUTO position.
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 will start at
reduced fan speeds to avoid blowing cold air into
the vehicle until warmer air is available. The system
starts out blowing air at 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 and temperature of
the vehicle.
4. Wait 20 to 30 minutes for the system to stabilize in
order for the system to regulate automatically. 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 will show the
interior temperature settings and the outside
temperature.
If the AUTO position is selected on the fan or mode
control, the system automatically controls the air
conditioning compressor. The A/C compressor will run
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, even at
near freezing outside temperatures. Press the A/C
button on the fan control to turn off the A/C. For
improved window clearing performance in defog or
defrost modes, the A/C compressor runs automatically.
h(AUTO RECIRCULATION):If the AUTO position is
selected on either the fan or mode control, the system
automatically controls the air inlet to supply fresh outside
air or recirculate 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 recirculation button when
the light is lit. For vehicles without rear climate controls,
press the outside air button to force outside air. The next
time AUTO fan or mode is selected, the air inlet will reset
back to AUTO operation.
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?(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’s Temperature Controls):Press these
buttons next to the fan control to manually increase
or decrease the temperature inside the vehicle.
wx(Passenger’s Temperature Controls):Press
these buttons next to the mode control to manually
increase or decrease the temperature for the front
passenger. If the passenger’s climate control system is
off, pressing one of these buttons turns it on.PASS (Passenger’s Climate Control):Press this
button to turn the passenger’s climate control systems
on or off. When the passenger’s climate control
system is on, the passenger’s temperature setting is
displayed. The temperature selected by the front
passenger also controls the rear system air temperature
unless the rear seat passengers select their own
comfort setting.
If the PASS button is pressed to turn the passenger
temperature setting off, the driver’s temperature
knob will control the temperature for the entire vehicle.
AUX:If your vehicle has a rear climate control
system, press this button to turn the rear climate control
fan on for automatic operation. After the AUX button
is pressed, the indicator light comes on. Press the button
again to turn the auxiliary fan off. SeeRear Climate
Control System on page 3-49.#(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 in AUTO,
the air conditioning compressor comes on automatically,
as necessary.
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.
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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 5 minutes.
Vehicle speed is above 32 mph (51 km/h)
for 2 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.
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. Use the oor/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.
W(Floor/Defog):Turn the control to this mode to
direct approximately half of the air to the oor outlets
and the remaining air is directed to the side window
outlets and to the windshield. When you select
this mode, 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):Turn the control to this mode to direct
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. Do not drive the vehicle until all the windows
are clear.
For professional vehicles, air will be allowed to ow
through the rear outlets. For quicker defrost, press the
AUX button on the front climate control system so
that the light is not lit.
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Charging System Light
This light will come on
briey when you turn on
the ignition key, 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 driving, there could be a problem
with the charging system. A charging system Driver
Information Center (DIC) message may also appear.
SeeDIC Warnings and Messages on page 3-75
for 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 you must drive a short distance with the light on,
be certain to turn off all the accessories, such as the
radio and air conditioner.
Brake System Warning Light
Your vehicle’s hydraulic brake system is divided into
two parts. If one part isn’t working, the other part can
still work and stop you. For good braking, though,
you need both parts working well.
If the warning light comes on, there is a brake problem.
Have your brake system inspected right away.
This light should come on briey when you turn the
engine on. If it does not come on then, have it xed so
it will be ready to warn you if there is a problem.
When the ignition is on, the brake system warning light
will also come on when you set your parking brake.
The light will stay on if your parking brake does
not release fully. If it stays on after your parking brake
is fully released, it means you have a brake problem.
United StatesCanada
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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, as a check to show it is working,
when the ignition is turned ON/RUN but the engine is not
running. 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 HOT – A/C (Air
Conditioning) OFF
This message displays when the engine coolant
becomes hotter than the normal operating temperature.
SeeEngine Coolant Temperature Gage on page 3-64.
To avoid added strain on a hot engine, the air
conditioning compressor automatically turns 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 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 5-27for more information.
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 3-63.SeeOverheated Engine Protection Operating Mode on
page 5-29for information on driving to a safe place
in an emergency.
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 5-27
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 5-27
andOverheated Engine Protection Operating Mode
on page 5-29. A chime also sounds when this message
is displayed.
ENGINE POWER REDUCED
This message displays when the engine power is
being reduced to protect the engine from damage.
There could be several malfunctions that might cause
this message. Reduced engine power can affect
the vehicle’s ability to accelerate. If this message
is on, but there is no reduction in performance,
proceed to your destination. The performance may
be reduced the next time the vehicle is driven.
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RADAR CRUISE NOT READY
This message displays when the Adaptive Cruise
Control (ACC) system will not activate due to a
temporary condition. Your vehicle does not require
service. If this message appears when you attempt to
activate the system, continue driving for several minutes
and then try activating the system again. SeeAdaptive
Cruise Control on page 3-19for more information.
RAINSENSE WIPERS ACTIVE
If your vehicle has Rainsense™ II wipers, this message
displays while this feature is active. SeeRainsense™
II Wipers on page 3-14for more information.
REMOTE KEY LEARNING ACTIVE
This message displays while you are matching a
Remote Keyless Entry (RKE) transmitter to your vehicle.
See “Matching Transmitter(s) to Your Vehicle” under
Remote Keyless Entry (RKE) System Operation
on page 2-5andDIC Operation and Displays on
page 3-70for more information.
REPLACE BATTERY IN REMOTE KEY
This message displays when the battery in the Remote
Keyless Entry (RKE) transmitter needs to be replaced.
To replace the battery, see “Battery Replacement” under
Remote Keyless Entry (RKE) System Operation on
page 2-5.
RIGHT REAR DOOR OPEN
This symbol appears with
this message.
This message displays when the passenger side rear
door is not closed completely. Make sure that the door
is closed completely.
SERVICE AIR BAG
This message displays when there is a problem with
the airbag system. Have your vehicle serviced by your
dealer/retailer immediately. SeeAirbag Readiness
Light on page 3-57for more information.
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SERVICE A/C SYSTEM
This message displays when the air delivery mode door
or the electronic sensors that control the air conditioning
and heating systems are no longer working. Have
the climate control system serviced by your dealer/
retailer if you notice a drop in heating and air
conditioning efficiency.
SERVICE BATTERY CHARGING
SYSTEM
This message displays when a problem with the
charging system has been detected. The charging
system light also displays on the instrument panel
cluster. SeeCharging System Light on page 3-60for
more information. Have your vehicle serviced by
your dealer/retailer.
SERVICE BRAKE ASSIST
This message displays if there is a problem with the
brake system. The brake system warning light and the
antilock brake system warning light may also be
displayed on the instrument panel cluster. SeeBrake
System Warning Light on page 3-60andAntilock Brake
System (ABS) Warning Light on page 3-61for more
information. If this happens, stop as soon as possible
and turn off the vehicle. Restart the vehicle and
check for the message on the DIC display.If the message is displayed or appears again when you
begin driving, the brake system needs service. See
your dealer/retailer as soon as possible. SeeBrakes
on page 5-37for more information.
SERVICE BRAKE SYSTEM
This message displays if the ignition is on to inform the
driver that the brake uid level is low. Have the brake
system serviced by your dealer/retailer as soon as
possible.
SERVICE LANE DEPARTURE SYSTEM
If your vehicle has the Lane Departure Warning
(LDW) system, this message may display to indicate
that the LDW system is not working properly.
If this message remains on after continued driving,
the system needs service. See your dealer/retailer.
SeeLane Departure Warning (LDW) on page 2-46for
more information.
SERVICE PARKING ASSIST
If your vehicle has the Ultrasonic Front and Rear
Parking Assist (UFRPA) system, this message displays
if there is a problem with the UFRPA system. Do not
use this system to help you park. SeeUltrasonic Front
and Rear Parking Assist (UFRPA) on page 2-40for
more information. See your dealer/retailer for service.
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