Rear window defroster not working, switch and fuse have been checked, not sure if there is a relay or where it is located. Camera, lights, and wiper on rear door all work fine. Suggestions on what to check next?

Thanks Dave. I checked for continuity on the glass and it is good. Also had good continuity between the harness connectors and the glass. I doubled checked the fuse which was still good and the box had power to the fuse. There was no voltage at the connectors to the glass with the defroster switch on. I suspect a broken wire somewhere or there’s a relay that’s gone bad.

I was driving yesterday and turned on the defrosters to melt frost on my side view mirrors and the rear defroster was working. About five hours later, I was driving home and turned the defrosters on again because it had snowed while the vehicle was parked and the defroster wasn’t working again. The only thing that I could think of was that since it’s been cold here in Michigan (-6 Fahrenheit this morning), I had put a trickle charger on the battery to help keep it charged as I don’t drive the vehicle every day. Could this be a sign that my battery needs to be replaced? Everything else seems to work fine like the heated wheel and seats, lights, infotainment center, etc.