Mercedes C Klasse Hybrid AC Problem

Sounds frustrating. Before diving into valves, have you considered simpler things? Sometimes it's like a power outage in your house; you check the main breaker first, not the wiring in the wall. Have you verified the AC compressor clutch is engaging? A faulty AC relay or a low refrigerant level due to a leak can also prevent the compressor from kicking on. It might be worth getting a pressure reading to rule that out before suspecting internal valve issues.

Thanks for the quick response. How would I check the AC compressor clutch engagement, and where is the AC relay located in this model? I've checked the refrigerant level via the low-pressure port, and it seems to be within the normal range, but I haven't had it professionally checked. Could a faulty pressure switch cause the system to completely shut down, even if the refrigerant level seems okay?

Alright, if you've already checked the refrigerant level and suspect the pressure switch, it's probably best not to tinker further. A faulty pressure switch can indeed shut down the whole system as a safety measure. Considering it's a model and you're suspecting valve issues, which can be complex and require specialized tools, my recommendation would be to take it to a workshop. It sounds like you're past the point of simple fixes, and you don't want to risk damaging anything further. Your suspicion of a valve issue aligns with the symptoms, and the repair cost could be around 1000€. Better to get a professional diagnosis.

Thanks for the advice! I took it to the workshop, and you were right. Turns out, a couple of valves within the AC system were faulty. They replaced the affected components, and the AC is now working perfectly again. The final bill came to 1000€, as expected. Appreciate the guidance!