XC60 Rear Window Heating Failure

I had a similar problem with my old BMW 3 Series. The window demister stopped working, and I also saw a weird error code. Have you checked your battery? In my case, a heavily discharged battery was the culprit. The car's computer can throw all sorts of errors when the voltage is low.

So you're saying a bad battery could cause these issues? I'm skeptical. How does battery health affect the window heater, and was the auto defrost affected?

With the BMW, the battery was so drained that it couldn't properly power all the systems, especially the high-drain ones like the heating coil for the rear window. I also noticed the car defrost was very slow. I'm not an expert, but it might be worth getting your battery tested. If it's not the battery, you should take it to a workshop to get it checked.

I checked the battery and it was degraded. I replaced it, and the rear window heating works now. It cost 290€. Thanks for the help.