Install Battery Siren VW G4 MJ 2001?

Hello,

I have a G4 2001 with a Comfort Control Unit (CCU) with part number 1J0 959 799 AH, index 02K. Can I connect the original VW alarm siren (part number 1J0 951 605, with a 3-pin connector) to terminal T15/3 of the CCU, as well as to the power supply and ground? Is it possible to reprogram the CCU to the -UK- configuration?
Currently, the horn (2-pin connector) is connected to terminal T15/11 of the comfort module or to ground.
I tried searching, but I couldn't find a clear or relevant post.
Have you ever done something like that before? What's the difference between a battery-powered siren and a horn?

Thank you for your help.