Engine error / check engine light + loud fan after vacation

[tobcio]

Hello everyone,

I have a problem with my 2011 C4 155 THP since Tuesday.

I came back from vacation on Monday after 2 weeks. A short round to go shopping (less than 5km). In the parking lot on the way home then when the engine starts "Engine error - please have it repaired" in the on-board computer (more or less the wording translated from german) + engine control light. Since then, the cooling system has been running at full power when the engine is started and continues to run at full power after the engine is switched off for some minutes. I never had anything like that even after hours of driving on the freeway in midsummer.
Other than that, I haven't found anything different or wrong.
Before the holiday I had not found any defects.

Has anyone ever had this? What could that be?
Due to the "longer" standing time, I might have thought of a marten bite or could something else have changed due to standing?

Thanks for every reply! <3