Atwood GC6AA-10E water heater - no response

[Lmitc210]

My Atwood GC6AA-10E water heater in my 2016 Scamp 13 is giving me problems. This is an electronic spark model that runs off of propane or 120v. The tank is full of water. When I try to start the water heater on either propane or electric, I get nothing. For propane operation, no ignition tries; on electric, I left the switch on for 1 hour; water is cold. I'm getting 12v to the switches, and every other propane appliance works fine. I'm not getting a lock-out light on the switch panel. The mini-ATO 2-amp fuse on the control board is good (as per a resistance test with a multi-meter).

I THINK it may be the thermal cutoff. Can the thermal cutoff be tested in some way to determine if it's bad? Or, is it safe to bypass the thermal cutoff briefly for testing purposes?

[Lmitc210]

After doing a bit more research, it looks like I can simply test the thermal cutoff for continuity. I think I could also just bypass (jumper) the contacts on either end where the thermal cutoff connects to confirm. If the thermal cutoff is good, I suppose I'll be looking at the thermostat and ECO sensors.

[Lmitc210]

Problem diagnosed: the thermal cutoff is bad. I removed the cutoff and checked for continuity, and got infinite resistance. I also fashioned a jumper and connected the thermostat directly to the brown control board wire and everything worked fine. I have a replacement thermal cutoff on order.