GMC 2003 C4C042, Owner'S Manual, Page: 190 / 386

3-21
Compact Disc Messages
If the disc comes out, it could be for one of the
following reasons:
D You’re driving on a very rough road. When the road
becomes smoother, the disc should play.
D It’s very hot. When the temperature returns to
normal, the disc should play.
D The disc is dirty, scratched, wet or upside down.
D The air is very humid. If so, wait about an hour and
try again.
If the CD is not playing correctly, for any of the above
reasons, try a known good CD.
If any error occurs repeatedly or if an error can’t be
corrected, contact your dealer.
Theft-Deterrent Feature
THEFTLOCK
R
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 Stereo
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.