Fiat Panda AC and Temperature Sensor Issues

Hmm, a defective temperature sensor could potentially cause those symptoms, but it seems a bit of a stretch for the AC not to engage. The sensor readings definitely affect engine cooling and performance, and that error message is a red flag. Have you checked the sensor's wiring or considered that the AC control unit itself might be faulty? It's not uncommon for those to fail, especially with that mileage.

Thanks for the reply. I haven't checked the wiring myself, to be honest, I'm not that experienced with car electrics. The AC control unit failing sounds expensive. Is there any way to test that before I start replacing parts? Or could it still be something simple like needing a sensor calibration?

Sensor calibration is unlikely to solve an AC issue, especially with a stored error code. While I can't say for sure without proper diagnostics, given the symptoms and the age of the car, I suspect the air conditioning control unit may indeed be defective, or at least contributing to the problem alongside the sensor. Best bet is a workshop with proper diagnostic tools.

Okay, thanks for the advice. I took it to a workshop, and you were right. The temperature sensor on the heat exchanger was indeed defective, but the main problem was the air conditioning control unit. They replaced both, and the total bill came to 980€. Everything is working again now.