[Jared66]

Follow the wire.

 

[Scott2373]

Your best bet is to get a hold of the wiring diagram online and figure out what it's wired to by tracing it. It might be a valet switch for an aftermarket alarm, or start playing with things and see if you can figure out if it turns anything on/off.

 

[Beastmaster]

I bet the PO had some extra lights or air pump and that's the switch. I think if you follow the wires, you'll find they run through the firewall forward and to the left of the steering wheel.

 

[UnlimitedJ33per]

Thanks guys, I'll follow it tomorrow. I figured if it wasn't immediately recognizable by members on this forum it must be aftermarket. Thanks!