I have a 2005 F-150 5.4L, and it's had 2 previous owners. I'm assuming it was the last owner, but somebody did a lot of electrical tinkering (wish I would've known beforehand)...

The other day, I found this thing lodged between the engine block and a piece of sheet metal under the hood. I can't, for the life of me, figure out what it is.

The two wires coming out of it appear to have been melted apart, but I think they were originally leading into the cab (possibly). It looks like something had been grinding on it for quite some time. I don't know if you can tell in the video, but there is a major gash that went through one side of the plastic shell.

All I can tell is that one half of the "egg" only contains a small circuit board, and the other half seems to be solid metal inside. I can't remove the metal from the lower half of the plastic shell.

I know this is vague, but here's a video. If anyone knows what this is, please let me know:
Thanks!

 

is the "solid metal" piece a magnet and heating element ? Maybe a block heater that held on by a magnet ?

 

looks like an aftermarket alarm siren

 

Thanks for the replies. I think this is probably the correct answer. Makes sense.


I don't think it's a block heater... It was fully enclosed in plastic, so the metal piece (I didn't test if it was magnetic) wouldn't have come into direct contact with anything.


It's gotta be an alarm siren. Now I remember that there was an alarm module installed under the DS dash, so it would make sense!


Thanks!