Arrived. found Microwave Oven unit had 115 F4 errors, customer said they couldn't cook in unit at all. checked and found switches all closing at appropriate times. did replace monitor switch and tested again. unit cooked multiple times okay, then started to shut down every time they wanted to cook. opened unit back up and found components very hot. checked and found cooling fan filter very clogged. did clean and monitored unit again. same issue was still present. made new connections on monitor switch and also hardwired a mulex connector that was brittle and breaking. also found secondary switch in poor condition. made repairs and tested. unit seems to be functioning okay at this time. okay for use.