GM Service Manual Online
For 1990-2009 cars only

ALT

Use the ALT button in order to access the RDS functions. When you press the ALT button, ALT displays on the screen. The ALT display prompts the user to make an RDS selection. If the user does not make a selection, the ALT display times out in 20 seconds. The radio dual function backlighting switches in order to illuminate the RDS functions under the following conditions:

    • The radio backlighting is on.
    • You press ALT

Message (MSG)

The MSG feature displays text broadcast by an RDS system. The MSG feature is only for domestic RDS receivers. Press the ALT button, then the MSG button in order to initiate the MSG feature.

If the currently tuned station is broadcasting messages, the system displays MSG. When you press MSG, the display shows the first 12/24 characters of information for 20 seconds. If you press MSG within 20 seconds the display shows the next 12/24 characters. The sequence continues until the system displays the entire message. The display returns to its appropriate contents under the following conditions:

    • If you do not change the display for 20 seconds
    • If you press any key other than MSG

Clock Time

The RDS Clock Time (CT) feature allows the broadcasting station automatically set the receiver. The default for CT is off. In order to enable the CT function, complete the following steps:

    • Press the ALT button.
    • Press either the HRS or the MIN button.

The display shows the current status. Press the MIN button in order to toggle through the following clock time states:

    • OFF
    • FIXED
    • AUTO

The display returns to its appropriate contents under the following conditions:

    • After 5 seconds
    • If you press any other key except MIN

The CT mode selection is available during all the radio modes in which the clock time may be set.

When using CT FIXED, you may update the clock time by the time zone of your choice. If you define a different time zone than the time zone you are currently in, the CT will appear to be inaccurate. When using the CT AUTO, the clock time will be inaccurate if the station sends the incorrect time.

In order to modify the clock time with the CT OFF, set the hours and minutes in the normal manner. While you are the in the CT FIXED mode, you may select the appropriate time zone by using the HRS key. The HRS key modifies the time zone in one half hour increments. The time zone displayed is the selected time zone. The display returns to the appropriate contents under the following conditions:

    • After 5 seconds
    • If you press any other key