Service engine soon light on 1996 Ford Taurus

Hi, Our 96 ford GL wagon, 175000 miles, engine is sound, the electrical is another story. Service engine soon light will not stay off. The radio started going off and on, the seat belt light on dash would come on and make a "ticking" kind of sound, the the steering went to REAL slippery feel, then I stopped, put it in park, put gear shift into drive and NO power steering,no power windows, no wipers. Mecahanic replaced a Trans Position SWT-S and a Heater blower resistor. Got car back, drove for 25 miles and Service engine soon came on again! Also, gas cap will not click shut, even a new one will not click shut. Any help out there? Thanks Karin

Asked by for the 1996 Ford Taurus
Hey, mine is doing the same thing!!! Did you find out what is happening? I just had transmission work done. Thanks.