Citroen C8 Auxiliary Heater Problem

I had a similar problem with my C8. The symptoms you describe strongly suggest a problem with the PTC heater. The electric auxiliary heater is designed to provide additional heat during cold weather. When it malfunctions, it can indeed cause the issues you're experiencing. I recommend you check the error code stored to identify whether it can point you in the right direction. Have you performed any specific diagnostic steps to confirm your suspicion?

I've checked the error memory using a generic OBD2 scanner, which indicated a fault related to the auxiliary heater circuit. I haven't delved into more specific diagnostics beyond that. What additional steps did you undertake to pinpoint the issue definitively?

Given that you've already identified a fault related to the auxiliary heater circuit via the OBD2 scanner, it does seem highly likely that the PTC heater is indeed the problem. In my case, the error code was quite specific, indicating a short circuit within the heater itself. Since you're experiencing similar symptoms and have a corresponding error code, I'd suggest taking your C8 to a qualified workshop for a more thorough diagnosis and repair. They'll have the necessary equipment and expertise to confirm the fault and replace the heater if necessary. The cost was approximately 350€ including installation.

Based on your experience and the error code I retrieved, I've decided to take the vehicle to a trusted workshop for a professional diagnosis and repair. They confirmed that the PTC heater was indeed defective and replaced it. The total cost was 350€. I'm happy to report that the issues have been resolved. Your input was instrumental in guiding me towards the correct solution!