GS Automatic Temperature Control Issue

It certainly sounds like a faulty interior temperature sensor or, more likely, a connection issue. I've seen similar symptoms in other vehicles where the cable or plug connection to the sensor was defective. Does the error code specifically point to the sensor itself, or does it indicate a circuit problem?

The error code points to the sensor. Is the replacement complicated or is there a way to check the cable and plug connection myself?

While the error code indicates the sensor, a faulty connection is common, especially with age. I'd advise against attempting repairs yourself unless you're experienced. Consider taking it to a qualified workshop for diagnosis and repair. They can confirm the fault and ensure proper replacement/repair.

Thanks for the advice. I took it to the workshop. It was indeed a defective plug connection, as you suspected. The total repair cost was 95€. Everything is working fine again.