Mistra Climate Control Failure

I had a similar problem on my old Opel Astra, though the symptoms were slightly different. The whole thing went haywire. No AC, heater stuck on full blast sometimes, other times nothing at all. It felt like the car was possessed. Have you checked the temperature sensor? In my case the temperature sensor was faulty and caused all that mess.

Interesting. Where exactly is that located on the Astra, and was it difficult to access? Could a faulty temperature sensor really cause all of these symptoms, including the climate control panel being completely unresponsive? I'm trying to understand the link. It feels more like an electronic fault, like the whole thing lost power. But if the sensor is a simple fix, I would try it.

On the Astra, the sensor was near the blower motor, a bit fiddly but doable. I'm not saying it's definitely the temp sensor with your Mistra, but the symptoms are close enough that it's worth checking. Given your description, though, it does sound like an electrical connection problem is more probable. My advice would be to go to a workshop and have them check the wiring harness and connections. It could save you a lot of time and frustration.

Thanks for the advice. I took your suggestion and brought it to the shop. Turns out it was indeed a faulty connector on the climate control unit, just like you thought. They cleaned the contacts and secured the connection. 95€ later, and everything is working perfectly again. Appreciate the help!