GMC 2010 Sierra 1500 Crew Cab Owner's Manual page 310

To set the time:
1. Turn the ignition key to ACC/ACCESSORY or
ON/RUN, then press the
radio on.
2. Press the button until the hour numbers begin to
flash, then turn the
the hour.
3. Press the button until the minute numbers begin
to flash, then turn the
decrease the minutes.
4. Press the button until the 12HR or 24HR time
format begins to flash, then turn the
change the time format.
5. Press the button again until the clock display
stops flashing to set the currently displayed time,
or wait until the flashing stops after five seconds
and the current time displayed automatically sets.
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button to turn the
knob to increase or decrease
knob to increase or
knob to
To set the time and date:
1. Turn the ignition key to ACC/ACCESSORY or ON/
RUN, then press the
2. Press the button to display HR, MIN, MM, DD,
YYYY (hour, minute, month, day, and year).
3. Press the softkey located under any one of the
tabs to change that setting.
4. To increase the time or date, do one of the
following:
Press the softkey below the selected tab.
Press the SEEK button.
Press the FWD button.
Turn the knob clockwise.
5. To decrease the time or date, do one of the
following:
Press the SEEK button.
Press the REV button.
Turn the knob counterclockwise.
button to turn the radio on.