Mini Clubman Defrost Issue

That sounds suspiciously like a faulty air distribution flap motor indeed! The error code pretty much confirms it. Before you resign yourself to replacing the whole unit, have you checked the simple things first? I'm talking about visually inspecting the wiring harness and the connector for the defrost flap motor. Sometimes corrosion or a loose connection can cause the exact symptoms you're describing – low heating output and windshield fogging galore! Especially since you mentioned it as the 'likely cause'. A faulty heater core usually presents with other symptoms, like coolant loss or a sweet smell inside the cabin. Have you noticed any coolant disappearing from the reservoir? Also, is the ventilation system filter clean? A blocked filter restricts airflow and reduces heating efficiency significantly. Just ruling out easy fixes before diving into potentially more complex (and expensive) repairs. It is always worth a shot!

Thanks for the quick response. I haven't noticed any coolant loss. I checked the ventilation system filter, it was replaced recently. You mentioned visually inspecting the wiring harness and connector, is there a common failure point I should be looking for specifically? Any usual location where corrosion could creep in?

Given that you've eliminated the other potential causes, and you've got the error code pointing directly at the flap motor, it does seem like the wiring or the motor itself is the culprit. While I can't pinpoint a specific 'common' failure point without physically inspecting the car, focus on areas where the wiring harness bends or is exposed to vibration. Check for chafing or any signs of damage to the insulation. Also, inspect the connector itself for corroded or bent pins. If you're not comfortable doing electrical diagnostics, I would strongly recommend taking it to a trusted mechanic who can properly diagnose and repair the issue. A multimeter and some electrical troubleshooting experience would be very helpful here. It sounds like the repair cost is acceptable. If you have any concerns about the climate control, heater core, or ventilation system, consider getting a professional opinion.

Just wanted to update, took the Mini to the shop. The cable to the defrost flap motor was indeed faulty. 95€ later, the windshield fogging is gone and the heater works properly again. Thanks for the advice!