GMC 2008 Savana Van Owner's Manual page 181

Changing the Time and Date Default
Settings
You can change the time default setting from 12 hours
to 24 hours or change the date default setting from
month/day/year to day/month/year.
To change the time or date default settings, follow these
instructions:
1. Press the MENU button. Once the
displays, press the pushbutton located under
the forward arrow that is currently displayed on the
radio screen until the 12H (hour) and 24H (hour),
and the date MM/DD (month and day) and
DD/MM (day and month) displays.
2. Press the pushbutton located under the desired
option.
3. Press the MENU button again to apply the selected
default, or let the screen time out.
Radio(s)
H
option
AM-FM Radio shown, Radio with CD (Base) similar
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