Mirai rear window heating issue

I also own a Mirai. I had a similar issue last winter. Does the light on the rear window heating button illuminate when you press it? If it does, does it stay on, or does it blink or turn off after a short period?

Yes, the light comes on when I press the button, and it stays on. I don't see any blinking or turning off.

Okay, in my case, the light also stayed on, but there was still no heat. Considering you also have an error code stored, and the windshield heating is also affected, it strongly points towards a battery issue affecting the heating system's performance. I'd recommend getting it checked out at a workshop.

Thanks for confirming. I took it to the workshop, and you were right; it was related to the battery. The repair cost was 290€. Now the rear window heater works perfectly again!