I had this problem with a Mazda 3. Disconnecting the hood switch stopped the alarm from randomly going off, but created another problem. A few weeks later I noticed my battery was being drained. I checked the circuit for the door monitoring system and noticed there was a high draw. I fixed the issue by soldering the wires of the hood switch together to complete the circuit.

I know this vid was posted year ago. Did alarm ever go again since then?

I did everything from disconnected horns and took out fuses. The problem went away for a while and during that time I was driving without horns. Now for some reason, it started to fuk with me again. So this time, I manually lock the doors and it still goes off by flashing lights buy eventually it stopped. After searching further, I make sure I take out all horn fuses that marked S which mean security alarm. I also did what this guy did with the hood hatch wire but I didn't splice them with green and yellow. I guess if the fuking thing started flashing my lights again then I will spice the wires.

I gotta 2013 venza started randomly alarming today

You try this