2003 CADILLAC CTS air conditioning

2-111
Engine Coolant Hot -- Idle Engine
This symbol appears
with the Engine Coolant
Hot
-- Idle Engine message.
This message will appear when the engine coolant
temperature is too hot. Stop and allow the vehicle to idle
until it cools down.
NOTICE:
If the Engine Coolant Hot -- Idle Engine message
appears on the DIC display, stop the vehicle as
soon as possible. Do not increase the engine speed
above normal idling speed. Severe engine damage
can result from driving a vehicle with an
overheated engine. See ªEngine Overheatingº in
the Index for more information.
Engine Coolant Hot -- AC (Air Conditioning) Off
This symbol appears
with the Engine Hot
-- AC
Off message.
This message displays when the engine coolant becomes
hotter than the normal operating temperature. 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 will turn back on. You can
continue to drive your vehicle.
If this message continues to appear, have the system
repaired as soon as possible to avoid compressor
damage.

2-116
Right Rear Door Ajar
This symbol appears
with the Right Rear Door
Ajar message.
When this message appears on the display, the right rear
door it means that the passenger's side rear door was not
closed completely. You should check to make sure that
the door is closed completely.Service AC (Air Conditioning) SystemThis symbol appears
with the Service AC
System message.
This message appears when the electronic sensors that
control the air conditioning and heating systems are no
longer working. Have the climate control system
serviced if you notice a drop in heating and air
conditioning efficiency.

3-
3-1
Section 3 Comfort Controls and Audio Systems
In this section, you'll find out how to operate the comfort control and audio systems offered with your vehicle.
Be sure to read about the particular systems supplied with your vehicle.
3
-2 Comfort Controls
3
-2 Climate Control System
3
-6 Air Conditioning
3
-6 Defogging and Defrosting
3
-6 Rear Window Defogger
3
-7 Ventilation System
3
-9 Climate Control Steering Wheel Controls
3
-9 Audio Systems
3
-10 Setting the Clock
3
-10 AM-FM Radio with Cassette Tape and
Compact Disc Player with Radio Data
Systems (RDS) and Digital Signal
Processing (DSP)3
-27 Navigation/Radio System (Option)
3
-27 Theft-Deterrent Feature
3
-28 Audio Steering Wheel Controls
3
-29 Understanding Radio Reception
3
-30 Tips About Your Audio System
3
-31 Care of Your Cassette Tape Player
3
-32 Care of Your Compact Discs
3
-32 Care of Your Compact Disc Player
3
-33 Diversity Antenna System

3-3

(Floor/Defrost): This setting directs airflow to
the floor ducts and toward the windshield, with some
air diverted toward the outboard outlets to defog the
side windows.


(Floor): This setting directs airflow
through the floor ducts. Some air is diverted
to the windshield and outboard outlets to
minimize fogging.
!~ (Fan): This switch adjusts the fan speed.
Press the up or down arrow to increase or decrease the
fan speed.
(Recirculation): Press this button to limit the
amount of outside air entering your vehicle. This is
helpful when you are trying to cool the air quickly or
limit odors entering your vehicle. Press this button again
to turn off the recirculation feature. If you notice the
windows fogging, turn off the recirculation feature.
Recirculation is not available in the defrost mode and
will automatically turn off after 10 minutes if
floor/defrost mode is selected.
(Defrost): Press this button to quickly remove
fog or frost from the windshield. This setting sends
most of the airflow to the windshield with a small
amount diverted to the outboard outlets to minimize
fogging. The air conditioning compressor may operate
in this mode.
A/C OFF (Air Conditioning Off): Press this button
to turn off the air conditioning compressor. AC OFF will
appear on the display. Press the button again to turn the
compressor back on. When the compressor is on, the
system will cool and dehumidify the air inside the
vehicle. The compressor cannot be turned off in
defrost mode.
(Driver's Temperature Switch): This switch is used
to adjust the air temperature for the driver's side of the
vehicle. To adjust the temperature, press the up or down
arrow located on the PWR button. The temperature will
increase or decrease with each press of an arrow.
The driver's set temperature is always displayed when
the climate control system is on regardless of whether or
not the system is in AUTO. See ªAutomatic Operationº
later in this section for more information on the
AUTO button.

3-4
(Passenger's Temperature Switch): This switch is
used to increase or decrease the temperature of the air
for the passengers independent of the driver's setting.
To turn the system on, press the PWR button located
on the passenger's side of the climate control panel.
To adjust the temperature, press the up or down arrow
on the PWR button. The temperature will increase or
decrease with each press of an arrow.
If the passenger's temperature switch is off, the driver's
temperature switch controls the temperature for the
entire vehicle.
The passenger's side temperature is only displayed
when the passenger's side temperature switch is on.
Automatic Operation
AUTO (Automatic Climate Control): This button is
used to select the automatic operation of the climate
control system. When the automatic operation is active,
AUTO will appear next to the fan and mode settings on
the display.There are three sensors in the climate control system.
One monitors the sun's solar radiation, another monitors
temperature of the air inside the vehicle, and a third
monitors the temperature outside the vehicle. The
climate control system will vary the fan speed, air
delivery mode and use of the air conditioning
compressor to maintain the set temperature based on the
information received from these sensors. See ªDriver's
Temperature Switchº and ªPassenger's Temperature
Switchº listed previously for more information on
setting a temperature.
To find your comfort zone, start with the 75
F (24
C)
setting and allow approximately 10 to 30 minutes for the
system to regulate. Adjust the temperature if necessary.
If you choose either the lowest temperature setting,
60
F (16
C), or the highest temperature setting,
90
F (32
C), the system will not cool or heat any
faster, but the system will stay at that setting without
regulating fan speed.
To avoid blowing cold air in cold weather, the system
will start at lower fan speeds until warm air is available.
The length of reduction depends on the outside air
temperature, engine coolant temperature or the time
since the engine was last started. As the engine coolant
warms up, the fan speed will gradually increase.

3-6 Air Conditioning
On hot days, open the windows long enough to let hot
inside air escape. This reduces the time it takes for your
vehicle to cool down. Then keep your windows closed
for the air conditioner to work its best.
While the system is in AUTO, it will use recirculation
as necessary to cool the air.
Defogging and Defrosting
When the mode switch is set for floor/defrost or the
defrost button is pressed, outside air will be selected
automatically. This helps clear the windshield more
quickly. Adjust the temperature and set the fan speed to
the highest setting. When the windshield is clear, adjust
the fan speed for maximum defrosting to a lower setting
or return to AUTO mode.
Recirculation is not available in the defrost mode, and
the air conditioning compressor cannot be turned off in
this mode.
For maximum side window defogging, turn the outboard
outlet thumbwheels to the side window defogger setting.
See ªVentilation Systemº later in this section for more
information on the outlet settings.
Rear Window Defogger
When the rear window defogger is turned on, the rear
window and both outside rearview mirrors are heated to
remove fog from the surface of the glass.
The rear window defogger
button is located on the
climate control panel to the
right of the defrost button.
Press the button to turn on the rear defogger. Press the
button again to turn the system off.
The system will automatically shut off after 10 minutes
unless your vehicle is traveling more than 30 mph
(48 km/h). If further defogging is desired once the
system is off, press the button again. The system will
automatically shut off after five minutes for any cycles
after the initial activation.

6-73
Air Conditioning Refrigerant
Capacity
If you do your own service work, you'll need the proper
service manual. See ªDoing Your Own Service Workº in
the Index for additional information. It is recommended
that service work on your air conditioning system be
performed by a qualified technician.
Air Conditioning
Refrigerant R134a 1.3 lbs. (0.59 kg). . . . . . . . . . . . .
Use Refrigerant Oil, R134a Systems
Normal Maintenance
Replacement Parts
Engine Air Cleaner/Filter A2029C*. . . . . . . . . . . . . . .
Passenger Compartment Air
Filter Element GM Part No. 25740404. . . . . . . . . . .
Engine Oil Filter PF2245*. . . . . . . . . . . . . . . . . . . . .
Spark
Plugs FGR8KQE0**. . . . . . . . . . . . . . . . . . . . . . . .
(GM Part No. 24425327)
Gap: 0.060 inches (1.4 mm)
Windshield Wiper Blade
(Shepherd's Hook Type) 22 inches (56.5 cm). . . . . .
*AC Delco

part number.
**Bosch part number.

7-22 Engine Cooling System Inspection
Inspect the hoses and have them replaced if they are
cracked, swollen or deteriorated. Inspect all pipes,
fittings and clamps; replace as needed. Clean the outside
of the radiator and air conditioning condenser. To help
ensure proper operation, a pressure test of the cooling
system and pressure cap is recommended at least once
a year.
Brake System Inspection
Inspect the complete system. Inspect brake lines and
hoses for proper hook
-up, binding, leaks, cracks,
chafing, etc. Inspect disc brake pads for wear and rotors
for surface condition. Inspect other brake parts,
including calipers, parking brake, etc. You may need to
have your brakes inspected more often if your driving
habits or conditions result in frequent braking.