hi...91 mustang lx convertible, brake lights wont come on, bulbs are fine, fuses are fine, what else is there to check? got any wireing diagrams?

Hello arcadelove069-- Haven't I warned you not to let your friend work on your 1991 Mustang. Friends mean well, but I want you to remember that a car's electrical system is as fussy as three little kids in the back seat. Did you ever see the time the Three Stooges got jobs as plumbers and water started shooting out of the telephone? Your remedy might come from a supplier called Crutchfield in Charlottsville, Va. They have turorial videos on almost anything to do with a car's sound system. Maybe you can find where your friend went wrong at-- http://www.crutchfieldadvisor.com/S-lgflOh9zW0q/. Good luck from Bovan.