99 E300 broken alarm sensor?

[TMAllison]

Does anyone recognize the broken switch in the photo. I find no obvious place it came from. Its a spring loaded toggle type of switch thats been disconnected since I got he car. Its not a part of the engine harness because that has been replaced.

It's mounted on the body just forward of the windshield washer reservoir with about 10" of play. The opposite end disappears into the engine compartment fuse box.

Am wondering if it is an anti theft switch in the event the hood is raised (with factory alarm activated nothing happens when hood is raised) or if has to do with alarm audio (if I trip the alarm or use the panic button, lights flash, but horns are silent).

Ideas?