crwdns2893792:0crwdne2893792:0 d west ,
Switch contacts in the latching mechanisms can fail or become intermittent. Printed circuit boards behind touch pads can flex causing printed circuits to develop cracks over time, resulting in the same type of failures. These include no heating or ventilation fan or intermittent operation, running with door open, etc. Hard to find or fix sometimes, usually it's poor design.