Mine went nuts a couple times on me. The last time was very early in the morning in a small nearby village as I was getting ready for a bike ride. I hate alarms anyway, but I opened the hood and ripped the horns out. I bought a new pair of horns and wired them directly to a relay, bypassing the computer alarm stuff.
It still has a false alarm every now and then. It just sits hopelessly flashing the lights. :-laf