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. ...

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Add-On Electrical Equipment
Notice: Do not add anything electrical to the vehicle unless you check with your dealer first. Some electrical equipment can damage the vehicle and the damage would not be covered by the vehicle' ...

Third Row Seats
If the vehicle has a third row seat, the seatback can be folded, and the entire seat can be tumbled or removed from the vehicle. ...

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. ...