rear locking module

So im a proud new owner of a 02 taco, and i recently found out that the moduel ontop of the rear diff is not connected. so im guessing i need a new one. i will try cleaning it when i get a chance to rip shit apart. but where can i find one to buy? cause my truck is a fucking 3x4 off roading. limited slip bull crap. and if anyone could check my pics out and tell me anything else you see. Thank you and this site is the greatest!

 

Ya your right i didnt know that there was such a thing as an open diff. I will have to get that e locker fixed. Thank you very much. Im just glad i have not got stuck in the mud yet. The front locker works, not the rear. thanks.