Had a customer's car alarm go off every time I touched the brake pedal
This was on a 2012 Civic last Tuesday. I was just doing a simple brake job in my home garage. The second I pressed the pedal to bleed the lines, the horn started blaring and the lights flashed. It scared me half to death. I spent 45 minutes checking everything, thinking I'd shorted a wire. Turns out the owner had some weird aftermarket alarm installed that tied into the brake light circuit, and the low fluid level from opening the bleeder valve triggered it. I had to call him to get the disarm code. Has anyone else run into an alarm system wired into something totally unexpected like that?
Check the brake fluid cap first thing. A lot of those cheap alarms have a simple float sensor hidden in there. Saves you a huge headache before you even pick up a wrench.