window switches and interior lights/ hazard lights not working

hey guy i just purchased a 2008 tundra 4.7 with 53k miles on it. the person her owned it before me. had an aftermarket trailer brake installed and hitch. me being me i decided the remove the brake controllers. i dont tow and will never tow a trailer. i took everything out. thinking nothing should go wrong. my windows( all door switches) do not work. my hazard lights dont come on anymore. interior lights dont come on. i started double checking everything and the only thing i cant figure out is. i got one connector that has nothing going to it. i don't see a spot to connect. all i know is it was connected to the trailer brake harness. it doesnt seem factory. but it has one big black wire that runs from the Toyota harness to that connector. at the moment. if i connect that wire back to the connector. there is still no where for the connector to connect. so im trying to see if yal wiring specialist can help me out. i have a hard time reading the wiring diagrams. they can get confusing. i attached come pictures to give a better under standing. i can get more to post. oh yeah this is under driver side dash