GMC YUKON XL 2004 Owner's Manual page 273

BAND (Alternate Frequency): Alternate frequency
allows the radio to switch to a stronger station with the
same program type. To turn alternate frequency on,
press and hold BAND for two seconds. AF ON will
appear on the display. The radio may switch to stronger
stations.
To turn alternate frequency off, press and hold BAND
again for two seconds. AF OFF will appear on the
display. The radio will not switch to other stations.
This function does not apply for XM™ Satellite Radio
Service.
Setting Preset PTYs (RDS Only)
The six numbered pushbuttons let you return to your
favorite PTYs. These buttons have factory PTY presets.
You can set up to 12 PTYs (six FM1 and six FM2) by
performing the following steps:
1. Press BAND to select FM1 or FM2.
2. Press the P-TYPE button to activate program type
select mode. P-TYPE and the last selected PTY will
appear on the display.
3. Turn the P-TYPE knob to select a PTY.
4. Press and hold one of the six numbered
pushbuttons until you hear a beep. Whenever you
press that numbered pushbutton, the PTY you
set will return.
5. Repeat the steps for each pushbutton.
RDS Messages
ALERT!: Alert warns of local or national emergencies.
When an alert announcement comes on the current
radio station, ALERT! will appear on the display. You will
hear the announcement, even if the volume is muted
or a CD is playing. If the CD player is playing, play will
stop during the announcement. You will not be able
to turn off alert announcements.
ALERT! will not be affected by tests of the emergency
broadcast system. This feature is not supported by
all RDS stations.
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