Heated Backlite and Mirror Timer
When the rear window defrost switch is pressed, a 10-minute timer is started and the GEM energizes a relay that provides battery voltage to the heated backlite (and the outside rear view mirrors if installed). The rear window defrost heats up to defog the rear window or melt accumulated snow or ice.The GEM de-energizes the relay when either 10 minutes have elapsed, the rear window defrost switch is pressed again, or the ignition switch is turned to OFF or ACCY. The 10-minute timer is temporarily halted if the ignition switch is turned to START, and resumes after the ignition switch is returned to RUN.