GMC Envoy Owner's Manual page 218

TRAF (Traffic): If TRAF appears on the display, the
tuned station broadcasts traffic announcements
and when a traffic announcement comes on the tuned
radio station you will hear it.
If the station does not broadcast traffic announcements,
press the TRAF button and the radio will seek to a
station that does. When a station that broadcasts traffic
announcements is found, the radio will stop seeking
and TRAF will appear on the display. If no station
is found that broadcasts traffic announcements,
NO TRAF will appear on the display.
If TRAF is on the display, press the TRAF button to turn
of the traffic announcements.
The radio will play the traffic announcement if the
volume is low. The radio will interrupt the play of a CD if
the last tuned station broadcasts traffic announcements.
This function does not apply to XM™ Satellite
Radio Service.
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 your vehicle and
it must be returned to your GM dealer for service.
LOCKED: This message is displayed when the
®
THEFTLOCK system has locked up. Take your 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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