Chevrolet Cruze Manual page 152

152 Climate control
Auxiliary heater
Air heater (Diesel vehicle only)
Quickheat is an electric auxiliary air
heater which warms up the
passenger compartment more
quickly.
Air vents
Adjustable air vents
At least one air vent must be open
while cooling is on in order to prevent
the evaporator from icing up due to
lack of air movement.
To open vent, turn the adjuster wheel
to Y.
Direct the flow of air by tilting and
swivelling the slats.