Lately my garage door craftsman 139.53615 SR will open/close mysteriousy. I have tried resetting the "code". I have no manual as I inherited the opener with the house. On th nmotor the is a yellow button which triggers a red light going on for about one minute. All remotes and opener on garage wall have no numbers, just a push button. Pushing the yellow button (if it changes the code) does not stop the problem! Any help/suggestions are appreciated!! FS