Expedition 4WD V8-281 4.6L SOHC (1998)
Heated Glass Control Module: Description and Operation
The GEM controls the heated backlight grid and heated mirrors by controlling the state of the heated backlight/mirror relay. When the heated
backlight/mirror switch is pressed, the GEM will activate the heated backlight/mirror relay. When the heated backlight/mirror relay is active, both the
heated backlight grid and heated mirror elements will be energized.
The GEM will deactivate the heated backlight/mirror relay when one of the following conditions is met:
The heated backlight/mirror switch is pressed when the feature is active.
Ignition switch state is changed from RUN to OFF/LOCK.
The 10 minute timing function is completed.
Ignition switch RUN position (12V on both RUN and RUN/ACC inputs).
Heated backlight/mirror switch (momentary contact to ground when switch is pressed).
Heated backlight/mirror relay control (grounded when activated, open circuit when deactivated).