Would not come out of park and hold flashing

Hello, I have read a lot of the question and answers on this site but cannot find a result. I have replaced neutral/park safety switch but car still flashing hold and will not shift from second on up. I have disconnected neg wire terminal over night and still flashing. Does anyone know how or if it is possible to reset yourself without scan tool? Anything other than what I have tried would be greatly appreciated. Thanks, TJ