Alarm Horn

Hi there

Please help me acessing to the horn.

I´ve a Octavia 1 (2002) and I think the horn is under the frontwindow under the black plate.

So how dissassembly this black plate to acess there? (where is the ac filter, etc).

The horn suddently stops to make noise, the lights blink but the horn is dead i think.

Would you like to give a link or a DIY to make the change ac filter? it´s the same thing

(the same local)

I´ll apreciate that helps.

r_kiko