Curious after a catalytic converter theft - presumably the car had been jacked up. Factory immobilizers of course are not for this sort of thing.
Imagine such a sensor itself is inexpensive, since things like game controllers and smartphones have the capability built-in (and back in the day probably could have just used a physical liquid mercury switch).
And would hope a tilt sensor wouldn't trigger false-alarms day-and-night like classic motion sensors.

 

most crooks are skinny enough to get under and do the job if it's a CUV/SUV. Cars sometimes need to be lifted.

Some folks install a shock sensor and wire it into the hood latch. This way if a "shock" is detected it will trip the car into thinking the hood was opened and blaringthe alarm.

There are lots of companies selling shock sensor kits that do the exact same thing for wheel theft, etc.

 

Thanks very much. Was not familiar with them.
It was a 1st gen TSX, so even stock is fairly low to the ground.
Never tried it, but if recalling correctly, hood latch "opening" sets the horn sounding, lights, etc., similar to a press of the key-fob panic alarm.

 

My grandmother had a tilt sensor on both of her last 2 S550s. I think it was OE & had a disable button in the event it needed to be towed.