Infiniti QX: Rear window and outside mirror defroster/windshield deicer (if so equipped) 
switch - Instruments and controls - Infiniti QX Owner's ManualInfiniti QX: Rear window and outside mirror defroster/windshield deicer (if so equipped) switch

Rear window wiper and washer switch
WARNING In freezing temperatures the washer solution may freeze on the rear window glass and obscure your vision. Warm the rear window with the defroster before you wash the rear window. C ...

Rear window and outside mirror defroster
To defog/defrost the rear window glass and outside mirrors, start the engine and push the switch 1 on. The indicator light 2 will come on. Push the switch again to turn the defroster off. ...

See also:

Brake temperature
In extreme circumstances, the HDC system may cause brake temperatures to exceed their pre-set limits. If this occurs the warning HDC TEMPORARILY UNAVAILABLE will be displayed in the message center ...

Battery Load Management
The vehicle has Electric Power Management (EPM) that estimates the battery's temperature and state of charge. It then adjusts the voltage for best performance and extended life of the battery. ...

Heated Mirrors
For vehicles with heated mirrors: (Rear Window Defogger): Press to heat the mirrors. See “Rear Window Defogger” under Dual Automatic Climate Control System  for more information. ...