Rear window and outside mirror defroster/windshield deicer (if so equipped) switch

Rear window and outside mirror defroster/windshield deicer (if so equipped) 
switch  - Instruments and controls - Infiniti QX Owners Manual - Infiniti QX

See also:

Before starting the engine
• Make sure the area around the vehicle is clear. • Check fluid levels such as engine oil, coolant, brake fluid and window washer fluid as frequently as possible, or at least whenever you refuel. • ...

Manual operation
Fan speed control Press the fan control buttons to manually control the fan speed. Press the AUTO button to return to automatic control of the fan speed. Temperature control Press the temperat ...

Automatic operation (AUTO)
The AUTO mode may be used year-round as the system automatically controls constant temperature, air flow distribution and fan speed after the desired temperature is set manually. To turn off the heat ...