Taken from the "Audio System Handbook" page 2-3.
Setting the audio display clock
1 Press and hold the MODE button until TA VOLUME is displayed.
2 Repeatedly press and release the MODE button until CLOCK SET is
3 While the hour format is flashing, use the seek up/seek down keys to
select either 12 or 24 hour format.
4 Press and release the MODE button.
5 If the 12 hour format has been selected, use the # key to select AM or PM
6 Using the keypad, enter the correct time. It should be noted that clock
time must be entered as four digits e.g. 0325 or 1525, when in 12 or 24 hour
7 To exit clock setting procedure, press and hold the MODE key until the
display reverts to audio mode.
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