Cadillac 2007 XLR - Manual (Page 183)

Rear Window Defogger
The rear window defogger uses a warming grid to
remove fog or frost from the rear window.
The rear window defogger will only work when the
engine is running.
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(Rear Window Defogger): Press this button
to turn the rear window defogger on or off. Be
sure to clear as much snow from the rear window
as possible.
The rear window defogger will turn off about
10 minutes after the button is pressed when
traveling less than 30 mph (48 km/h). If turned
on again, the defogger will only run for about
five minutes before turning off. The defogger can
also be turned off by pressing the button again
or by turning off the engine.
The heated outside rearview mirrors will heat to
help clear fog or frost from the surface of the
mirrors when the rear window defogger is on.
The rear window defogger and heated mirrors are
automatically disabled when the retractable
hardtop is moving or down.
Notice: Do not use anything sharp on the
inside of the rear window. If you do, you could
cut or damage the warming grid, and the
repairs would not be covered by your warranty.
Do not attach a temporary vehicle license,
tape, a decal or anything similar to the
defogger grid.
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