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:

Driving safety precautions
Your INFINITI is designed for both normal and off-road use. However, avoid driving in deep water or mud as your INFINITI is mainly designed for leisure use, unlike a conventional off-road vehi ...

Warning systems switch (if so equipped)
The warning systems switch is used to turn on and off the warning systems (Forward Collision Warning (FCW), Lane Departure Warning (LDW) and Blind Spot Warning (BSW) systems) that are activa ...

Front seat-mounted side-impact supplemental air bag and roof-mounted curtain side-impact and rollover supplemental air bag systems
The side air bags are located in the outside of the seatback of the front seats. The curtain and rollover air bags are located in the side roof rails. These systems are designed to meet volu ...