1996 Toyota Supra Owners Manual - Page 54

Make sure you turn the defoggers off when the surfaces are clear. Leaving the defoggers on for a long time could cause the battery to discharge, especially during stop-and-go driving. The defoggers are not designed for drying rain water or for melting snow. If the outside rear view mirrors are heavily coated with ice, use a spray de-icer before operating the switch. NOTICE When cleaning the inside of the rear window, be careful not to scratch or damage the heater wires. 48