Technical Multipla horn on constantly!

[Dr Denzelino Poblinski]

Woke up to the sound my Multi's horn just blasting away at 1am to it's hearts content, I flipped the bonnet in my underpants and yanked out the wires like John Maclean diffusing a time-bomb. Any ideas?

 

[Dcthebear]

Relay stuck in closed position would be first guess. Try changing it. Also is an alarm system fitted that works the horn? If so check the alarm batteries, usual way for it to tell you to change them.