Where would you find a free wiring diagram online for a 1990 Cadillac Brougham 5.7 liter?
All data type it in your search engine
alldata is NOT FREE..you can purchase alldata for just your vehicle for a minor fee..but it is not free..there are no free wiring diagram sites..believe me...that stuff is a money maker..nobody does it for free.
You can try going onto a car forum and asking the mechanic there.they sometimes will provide you with something for free.
Try Cadillacowners.com forums..then go to the subforum for broughm..
City and County libraries often contain auto repair manuals. There is a posssibility of finding your info there.