vickeyflee

I have a 2001 Acura CL that i bought about 6 months ago and the tranny had been replaced when i bought it. The guy i bought it from said the CEL light was not on before he changed the tranny but is now. The codes were both O2 sensors which i replaced the upstream one but not the down stream. After unplugging the negative cabel to reset it the CEL went off then came back on i rechecked the codes and the down stream code is one but now i got P1768 manufacturer contrl transmission and i have searched high and low on the internet and can't find any information can any one tell me what this code is and how to fix it?