I had the dealer install a Ford alarm on my convertible and it works fine when the doors are jimmyed or when the glass is broken or the car is jostled. But... it does not sound and alarm if someone reaches in while the top is down and takes something from the console.

Has anyone added a motion sensor that doesn't go off when someone walks near your car? I'd be interested in something that can be mounted out of sight - perhaps behind the dashboard.

 

I have the factory installed alarm with the motion sensors. If someone in the back seat reaches into the front, that sets the alarm off.

Don't know if the motion sensors are on if the top is down.

 

I have an 07, according to the owners manual the motion sensors (located in the rearview mirror) only work with top and windows up. I agree, I'd like them to pick up someone leaning in while top is down