Citan Diesel Overheating and Air Flap Issues

I understand you are experiencing issues with your Mercedes Citan's active air flap. The symptoms you describe, namely the check engine light and engine overheating, do indeed correlate with a potential malfunction in the cooling system's air intake regulation. To ensure I fully grasp the situation, could you please elaborate on the circumstances under which the overheating occurs? For instance, does it happen primarily during city driving, highway cruising, or both? Also, were there any other codes registered during the diagnostic scan besides the active air flap fault?

Overheating is mostly in city driving, especially in traffic. The diagnostic scan only showed the air flap fault code.

Thank you for the additional information. Given that the overheating primarily occurs during city driving and the diagnostic scan exclusively registered the active air flap fault code, it is highly probable that the grille shutter is indeed the source of your woes. These shutters play a vital role in regulating airflow through the radiator, particularly at lower speeds. A malfunctioning electromechanism can prevent them from opening properly, leading to inadequate cooling and subsequent overheating. Given the complexity of modern engine management systems, I would strongly recommend consulting a qualified technician for further diagnosis and repair. The estimated cost of 590€ you mentioned for the repair appears to be within the expected range for such an issue. A workshop should be able to confirm the diagnosis and replace the faulty components.

Thanks for the advice. Took it to a workshop, and you were right. The active air flap electromechanism was defective. Repair cost was exactly as expected. Problem solved.