Underhood mystery (mercury?) switch

Fissel

New Member
Original poster
Joined
Feb 7, 2024
Messages
11
Location
Eagle River, Alaska
Anyone know what this is? Noticed a switch(?) with the wire pulled out on my 1998 TJ & I don't know what it is or what it does. Any help is appreciated.

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Attach the wire back and solve the mystery. I want to see if the bulb works. :unsure:

Yeah, It looks like a light with a bulb, not a mercury switch.

Whatever it is it's gotta be aftermarket along with that broken wire. I would hope there's something better than the only visible screw to attach that wire to because that screw is definitely grounded and that wire is probaly hot either all the time or when switched on and there's a good chance that there's no fuse involved there because you never know what any previous owner has done.
 
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It's a mercury tilt switch, and as others have said not a stock part on a TJ. They are typically used to trigger a light or an alarm. Trace the disconnected wire back and see where it leads.
 
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Man, I just double checked on my PC and unlike what my phone showed me I believe you are correct about it being a mercury switch.

Maybe that switch just finishes a circuit by creating the ground which sets off a siren to scare away whoever thought they'd get a free battery to trade for some Meth.
 
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Thanks all for the help. As long as this isn't some factory item I need to worry about, I'll tape the wires & remove the switch. Vehicle definitely doesn't have an alarm now, but I'm the third owner so who knows what it had previously.

Makes me feel better as I was frustrated I couldn't find anything about it when looking over the factory wiring diagram.
 
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