1993 ford aeromax road tractor with series 60 Detroit engine fan will not come on when engine heats up can anyone help?

I have 1993 Ford areomax l-9000 with a 350 cat, i replaced the fan sensor no luck, ford said on the fire wall there will be a block with about 10 male ends on it, they said there are one hot wire to each block, it noted ford wiring to rust or brake at the male ends.

they said to replace the block and the wiring ends. i just put a switch on the dash and ran a wire to the fan for now and it work great as long as you don't forget to turn it on win you need to