Audi 100 C4 beeps and shows warning signal for defective bulb?

Hello, for the past few days, my Audi 100 C4 has been emitting an audible warning signal and a faulty headlight symbol more and more frequently, although all the headlights work. It seems to be something electrical or wiring related. I'm fairly certain it's the taillights, as the warning signal occurs more frequently when the trunk is closed firmly. It also always sounds when cornering, especially when cornering on the left (centrifugal forces, false resistance?). Perhaps someone knows the problem or has a good tip on where to start looking 🙂