We have a 2004 OBW with about 140,000 miles. Recently the door locks have been giving us trouble. Push the button on the key fob and the locks will repeatedly lock and unlock and finally stop locked. Then we have to open the door manually with the key. Sometimes we can't even open the back doors because they stay locked until you climb over the seat to unlock them manually. Sometimes when you turn the ignition off the doors will lock and only open when you manually unlock them. Then all is well for a few weeks until it starts up again. has anyone had this issue and know where to start looking?