[Richard]

I agree one of the contacts in the contactor is not making the circuit. Yes, one could replace the contactor. You could also get access to the actual contact and clean it up a bit. If you do that, it will work for a while, but my experience is that once the contact is compromised, it is a short time before it stops working again. Way back, all instrument techs carried a burnishing tool with them. It was used to work harden the surface of the contact to make it last longer.

My guess is that the combination of cold weather requiring extra heaters in the coach drawing increased amperage, low voltage on the grid because everyone else is doing the same, and the cold making the contactor old and creaky like me all contributed to the contacts burning up.

Once Doug has tried the Russ suggestions to exercise it, if it didn’t come back to life, I am hard wiring until it is warm enough to comfortably work on it. Then I am replacing the entire Xfer switch. I upsized mine to 90 amp just for overkill. That switch takes a beating.

While we are thrashing this subject, it is a good time to caution about switching from generator to pedestal under load, or vice versa. It absolutely wreaks havoc with the transfer switch. As one set of contacts open and the other set closes, an intense arc is created which burns up the contacts.