Buick LaCrosse Owner's Manual page 198

Clears the
windshield of fog or frost more
quickly. Air is directed to the
windshield.
For best results, clear all snow and
ice from the windshield before
defrosting.
For eAssist vehicles that have the
auto defog feature, auto stops can
occur in defrost mode. In this mode,
the auto stops are shorter and less
frequent than other air delivery
modes to prevent instant fogging.
Press to turn the air conditioning
system on or off. If the climate
control system is turned off or the
outside temperature falls below
freezing, the air conditioner will
not run.
Pressing this button cancels
automatic air conditioning and turns
off the air conditioner. Press AUTO
to return to automatic operation and
the air conditioner runs
automatically as needed. When the
indicator light is on, the air
conditioner runs automatically to
cool the air inside the vehicle or to
dry the air needed to defog the
windshield faster.
For eAssist vehicles, an auto stop
may occur if the climate control
system determines the a/c
compressor can be shut off and still
maintain comfort levels with minimal
windshield fogging.
This setting balances
fuel economy and air conditioning
comfort. In warm weather
conditions, auto stops may occur
more frequently and the vehicle
interior may be warmer as
compared to the comfort air
conditioning. The eco a/c setting
allows higher humidity inside the
vehicle and window fogging before
the engine restarts.
Pressing the button during an
auto stop will restart the engine to
prevent window fogging. To reach
comfort levels quickly during an
auto stop, the engine will restart if
the air conditioner is off and the
AUTO, eco , or A/C is selected.
The engine also restarts if the
pressed on and the system is set to
AUTO, eco , or A/C.
If temperature controls are adjusted
cooler by more than 1°C (1°F)
during an auto stop, the engine will
restart to ensure that comfort is
reached.
Press to change to
automatic control of air recirculation
inside the vehicle. When the auto
recirculation indicator light is on, the
air is automatically recirculated as
needed to help quickly cool the air
inside the vehicle.
In auto recirculation control, the Air
Quality Control system may operate
when pollution is detected. To adjust
the sensitivity of the Air Quality
Control, see Climate and Air
Quality under
is
.