Skoda Yeti Diesel Overheating Issue

Whoa, overheating on a Yeti isn't something you hear about every day, even with the diesel. That active air flap issue sounds plausible though. The check engine light is a classic symptom. Have you scanned the car for any specific fault codes? That would pinpoint the problem. Also, are you sure the air intake isn't blocked by debris? I had a similar scare once with a plastic bag stuck in the grille shutter of my Octavia; it caused some weird temperature fluctuations.

Thanks for the quick reply! Yes, I used my OBD scanner and it threw a P05A0 code, which pretty much confirms the active air flap issue. I visually inspected the air intake and grille shutter, and I couldn't see any obvious obstructions. Is there a way to test the electromechanism itself to be sure before I start buying new parts?

P05A0 pretty much confirms it. It's almost certainly the active air flap. While you could try probing the motor with a multimeter, honestly, it's probably seized internally. Given the mileage and the fault code, I'd say it's time to replace it. A faulty active air flap can definitely cause car overheating as it messes with the air intake and cooling. Get it sorted before you damage the engine! I suggest you go to the workshop. I once tried to fix this myself, and it cost me more time than it was worth. Some things are better left to the pros!

Just to conclude this, the active air flap motor was indeed broken. I had it replaced at a good garage; the whole thing cost me 590€. The engine light is off, and the Yeti is no longer overheating. Thanks for confirming my suspicions and pointing me in the right direction, I appreciate it!