My rear-right turn signal has started doing this odd thing where it will no longer function mid-drive. Turn the car off for a few hours, and it'll start working again. Anyone else experienced this? Clearly I can rule out a bulb or fuse issue...

 

Havn't had THAT particular problem, but rest assured, it's an electrical module problem (the XE it STUFFED with swap-out modules for every little function---it's almost goofy),
and repair is simple.

I had a moonroof problem. The roof simply would stop operating in the middle of a summer morning. But if I left it in the hot sun, by end of day, the moonroof would function again.
I thought it was a loose wiring harness. Turned out the car needed to be hooked to one of those diagnosis machines, and the machine told the mechanics to replace the sunroof control module.

Simple job. All warrantied.
Take the car in to a service center---this is after all technically a safety issue, since the car can't function the way the Law and police require every car to function.
As long as they have the diagnosis machine available, they'll know exactly where that electrical issue is.