Theft-Deterrent Feature (Non-Rds Radios); Understanding Radio Reception; Care Of Your Cassette Tape Player - GMC 2003 GMT560 T-Series Owner's Manual

Theft-Deterrent Feature
(Non-RDS Radios)
®
THEFTLOCK is designed to discourage theft of your
radio. The feature works automatically by learning
a portion of the Vehicle Identification Number (VIN). If
the radio is moved to a different vehicle, it will not
operate and LOC will be displayed.
®
With THEFTLOCK activated, your radio will not
operate if stolen.

Understanding Radio Reception

AM
The range for most AM stations is greater than for FM,
especially at night. The longer range, however, can
cause stations to interfere with each other. AM can pick
up noise from things like storms and power lines. Try
reducing the treble to reduce this noise if you ever get it.
FM
FM stereo will give you the best sound, but FM signals
will reach only about 10 to 40 miles (16 to 65 km).
Tall buildings or hills can interfere with FM signals,
causing the sound to come and go.

Care of Your Cassette Tape Player

A tape player that is not cleaned regularly can cause
reduced sound quality, ruined cassettes or a damaged
mechanism. Cassette tapes should be stored in their
cases away from contaminants, direct sunlight and
extreme heat. If they aren't, they may not operate
properly or may cause failure of the tape player.
Your tape player should be cleaned regularly after every
50 hours of use. Your radio may display CLN to
indicate that you have used your tape player for
50 hours without resetting the tape clean timer. If this
message appears on the display, your cassette
tape player needs to be cleaned. It will still play tapes,
but you should clean it as soon as possible to
prevent damage to your tapes and player. If you notice
a reduction in sound quality, try a known good
cassette to see if the tape or the tape player is at fault.
If this other cassette has no improvement in sound
quality, clean the tape player.
For best results, use a scrubbing action, non-abrasive
cleaning cassette with pads which scrub the tape
head as the hubs of the cleaner cassette turn. The
recommended cleaning cassette is available through
your dealer (GM Part No. 12344789).
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