Cadillac cts User Manual

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.

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 “Ventilation System” later in this section for more
information on the outlet settings.

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.