I have a 99 ford windstar tranny manufactory malfunction code?

I have a 99 ford windstar in which i replaced the torque converter because the odb light keeps blinking. Now it started to do it again. What else could be the problem?I have a 99 ford windstar tranny manufactory malfunction code?what code does it have there are many tcc related codes some are performance related some are electrical, there is no way to tell without code should be a P code.