GMC 2006 Sierra - Manual (Page 307)

Theft-Deterrent Feature
THEFTLOCK ® is designed to discourage theft of
your vehicle’s 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 LOCKED will appear on the display.
When the radio and vehicle are turned off, the blinking
red light indicates that THEFTLOCK
® is armed.
With THEFTLOCK ® activated, the radio will not operate
if stolen.
Audio Steering Wheel Controls
If your vehicle has this feature, some audio controls can
be adjusted at the steering wheel. They include the
following:
g
(OnStar ® /Mute): If your vehicle has OnStar, press
this button to interact with the OnStar system. See the
OnStar
® System on page 2-73 in this manual for more
information.
If your vehicle does not have OnStar, press this button
to silence the system. Press it again, or any other radio
button, to turn on the sound.
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