Pontiac 2003 Aztek Owner's Manual page 217

For DAB (Canada only, if your radio is equipped with
DAB), when the TRAF button is pressed, DAB does not
seek to a station that broadcasts traffic. DAB only
checks the current frequency for traffic support.
Traffic Interrupt Feature: Your radio can interrupt the
play of a cassette, CD, or XMTM, or DAB station.
Press the TRAF button. The radio will seek to a station
that broadcasts traffic announcements. When the
radio finds a station that broadcasts traffic
announcements, it will stop. Brackets around TRAF will
appear on the display. When a traffic announcement
comes on the station that was found, you will hear
it. When the traffic announcement is over, the radio will
resume play of the cassette, CD, or XMTM, or DAB
station. If no station is found, NO TRAFFIC will appear
on the display.
Radio Messages
CALIBRATE: Your audio system has been calibrated
for your vehicle from the factory. If CALIBRATE appears
on the display, it means that your radio has not been
configured properly for your vehicle and must be
returned to the dealership for service.
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