Mercedes B Klasse climate control problem

Hmm, that sounds frustrating. Could be a few things, honestly. Have you checked the fuses related to the HVAC system? Sometimes it's something simple like that. Air conditioning not switching on definitely points to something electrical, but without proper diagnostics, it's hard to say. Do you know how to check the voltage on the connector to see if there is a problem?

Good shout on the fuses, I'll definitely check those first thing. But if the fuses are all good, what next? I'm just trying to avoid taking it to the workshop if it's something I can sort myself. I'm wondering if it could still be a faulty temperature sensor even with good fuses? Or perhaps a more fundamental issue with the main control unit?

Yeah, it could be the temperature sensor but without proper tools, it's going to be tough to diagnose for sure. If the fuses are fine and you're still having issues, and especially since you're seeing an error code, I'd honestly suggest getting it looked at. Better safe than sorry, right? Could save you money in the long run by preventing further damage. It could be a more complex electronic fault than you realize.

Thanks for the advice, I think you're right, I'm probably out of my depth here. Turns out it was indeed a defective cable/plug connection, just like the error memory suggested. Cost me 95€ to get sorted, which isn't too bad all things considered. Appreciate the input!