GMC 2006 Sierra 1500 Pickup Owner's Manual page 269

RDS Messages
INFO (Information): If the current station has a
message, the information symbol will appear on the
display. Press this button to see the message. The
message may display the artist, song title, call in
phone numbers, etc.
If the entire message is not displayed, parts of the
message will appear every three seconds. To scroll
through the message, press and release the INFO button.
A new group of words will appear on the display after
every press of the button. Once the complete message
has been displayed, the information symbol will
disappear from the display until another new message is
received. The last message can be displayed by pressing
the INFO button. You can view the last message until a
new message is received or a different station is tuned to.
Radio Messages
CAL ERR (Calibration Error): The audio system has
been calibrated for your vehicle from the factory. If CAL
ERR appears on the display, it means that the radio has
not been configured properly for the vehicle and must be
returned to your GM dealer for service.
LOCKED: This message is displayed when the
®
THEFTLOCK system has locked up. Take the
vehicle to your GM dealer for service.
If any error occurs repeatedly, or if an error cannot be
corrected, contact your GM dealer.
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