Like I did years ago with the original UMC (that was potted), here is the GEN2 unit opened up. This one failed at the relay connection.
It is a laughably [expletive] design overall. They seemed to have properly incorporated many improvements over the previous version, while introducing new failure modes. Did you notice how poorly the wires were handled with the ultrasonic weld? Strands just loose. Fortunately, this is the very first Tesla UMC that isn’t potted. You can actually open it up and repair it, although it’s not easy. It’s designed to be quick and simple to slap together by low paid Mexican workers in Chihuahua, Mexico.