Astra central locking malfunction

That's a pain! Does the key fob still seem to be working? Any signs of life from the car alarm or security system? Have you tried the manual key entry just to rule out a completely dead battery or something simple?

Yes, the key fob is transmitting. I can see the light. What do you mean by 'signs of life'?

Okay, good to know about the key fob. By 'signs of life', I meant any beeps or flashes when you press the lock/unlock buttons, just to confirm the car is at least trying to do something. Since that's not the case, it sounds like a deeper issue. It might be time to have it checked at a workshop.

Thank you for the advice. The issue was a defective cable connection to the central locking module. Repair cost 95€.