Pontiac 2004 GTO - Manual (Page 153)

Backglass Antenna
The AM-FM antenna is integrated with the rear window
defogger, located in the rear window. Be sure that
the inside surface of the rear window is not scratched
and that the lines on the glass are not damaged. If
the inside surface is damaged, it could interfere
with radio reception. Also, for proper radio reception,
the antenna connector at the top-center of the rear
window needs to be properly attached to the post on
the glass.
Notice: Using a razor blade or sharp object to
clear the inside rear window may damage the rear
window antenna and/or the rear window defogger.
Repairs would not be covered by your warranty.
Do not clear the inside rear window with sharp
objects.
Notice: Do not apply aftermarket glass tinting with
metallic film. The metallic film in some tinting
materials will interfere with or distort the incoming
radio reception. Any damage caused to your
backglass antenna due to metallic tinting materials
will not be covered by your warranty.
Because this antenna is built into your rear window,
there is a reduced risk of damage caused by car washes
and vandals.
If you choose to add a cellular telephone to your
vehicle, and the antenna needs to be attached to the
glass, be sure that you do not damage the grid lines for
the AM-FM antenna. There is enough space between
the lines to attach a cellular telephone antenna
without interfering with radio reception.
Do not apply aftermarket glass tinting to the back glass.
The metallic film in some tinting materials will interfere
with or distort the incoming radio reception. Care
must be taken when cleaning the rear window because
it breaks in the resistive material heating element
and will adversely affect radio and defogger
performance. See your dealer for details.
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