GMC Cadillac CTS 2004 Owner's Manual page 150

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.
Manual Operation
yN z
(Mode): Pressing the mode switch and
changing the mode cancels automatic operation and
places the system in manual mode. Press AUTO
to return to automatic operation.
The outboard air outlets will always receive air flow
regardless of the mode selected. See Outlet
Adjustment on page 3-34 to change this airflow
from the outboard outlets.
To change the current mode, select one of the following:
Y
(Vent): This mode directs air to the instrument
panel outlets.
\
(Bi-Level): This mode directs approximately half
of the air to the instrument panel outlets, and then
directs most of the remaining air to the floor outlets.
Some air may be directed toward the windshield.
In automatic operation, cooler air is directed to the
upper outlets and warmer air to the floor outlets.
3-30
[
(Floor): This mode directs most of the air to the
floor outlets with some air directed to the outboard
outlets (for the side windows), and a little air directed to
the windshield.
The mode switch can also be used to select the defog
mode. Information on defogging and defrosting can
be found later in this section.
y9z
(Fan): Press this switch to increase or
decrease the fan speed. Pressing this switch cancels
automatic operation and places the system in manual
mode. Press AUTO to return to automatic operation.
If the airflow seems low when the fan speed is at
the highest setting, the passenger compartment air filter
may need to be replaced. For more information, see
Passenger Compartment Air Filter on page 3-35
and Scheduled Maintenance on page 6-4.
h
(Recirculation): This mode keeps outside air from
coming in the vehicle. It can be used to prevent outside
air and odors from entering your vehicle or to help heat or
cool the air inside your vehicle more quickly. Press this
button to turn the recirculation mode on or off. The
air-conditioning compressor also comes on.
Recirculation is not available in the defrost mode and
will automatically turn off after 10 minutes when defog
is selected.