Back-up switch plugs into????

i have a 96 xj with 5 sp manual tranny. back up lights don't work so I checked the back-up light switch and it's fine, but not plugged into anything, the cord is short so I assume that the other connector is near by but can't find a thing except vent tubes....should this be connected to something?
any pics would be HUGE

TIA

doug

Well, yeah it needs to be plugged into something. The wiring harness comes down the passenger side of the firewall, across the top of the tranny, and ends at the speedo sensor at the transfer case. Might just need to get behind the xfer case and look up high.