My 95 Taurus blows blinker fuses everytime I put it in R and step on the brake...what do I do to fix this?

I've checked everything I can think of, had it tested at AutoZone, they came up with zilch. I have checked wire connections in the taillights. I am at my wits end and now the check engine light is coming on, don't know if it's related and therefore a larger electronics problem. Help! My teenage daughter will soon need to drive this car and we live off a very busy highway, she CAN'T be w/o blinkers, it will cause a wreck or get her a ticket. FYI - if you put the car in R and step on the gas to back up, put it in N and THEN step on the brake it won't blow the fuse, only if you're in R when you step on the brake will it blow the fuse. I've even taken the steering column apart and cleaned the connections...what now?