Cadillac 1994 DeVille Owners Literature page 168

REAR WINDOW DEFOGGER
Push this button to turn
on the rear defogger.
With it, your rear
window and both
outside rearview
mirrors are heated.
The system will automatically shut off after 10 minutes. If further
defrosting is desired, simply push the button again.
NOTICE:
Scraping the inside of your rear window could cut and damage
the heating grids. Your warranty would not cover this damage.
And don't put decals there; you might have to scrape them off.
Electronic Solar Sert$opi
The Electronic Solar Sensor is part of the Electronic Climate Control
System.
The sensor monitors
the sun's solar
radiation. The
Electronic Climate
Control uses this
information to
automatically make
the necessary
temperature and air
flow adjustments to
maintain your comfort.
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