I intentionally turned mine off. On / Off 3 times without starting then on then get one chime from the door locks and it is disabled. The sequence is suppose to be in the owners manual. I never found it, but there is a thread on it here on TDR.
Did you do a sequence something like that by accident?, might be a reason.
You could probably do the sequence and turn the automatic door lock feature on or back on (if they are still functioning in th first place, which is probably what you are trying to figure out).