pcm 0745 the TCC is stuck off. what is the TCC and where?

Question:
1999 Cadillac devillie, pcm 0745 the TCC is stuck off. what is the TCC and where? I have tried the TPS at first from running symptoms but after learning to get the codes and reading the manual it says that its the TCC but do not know the actually definition of that abbreviation.I have a 98 with good trni was thinking of changing whole trani but alot of work!It seems to be fine in all gears but at acceleration it hesitates in overdrive and at stop lights the rpms are crazy up n down but if you place it in neutral it stops.Almost replaced the VSS but that would come with speedometer issues always?

Answer:
tcc stands for torque converter clutch. this is a solenoid that controls your torque converter. when it see the right parameter the torque converter gets lock up for better fuel economy on the highway. only on the hwy is the converter is suppose to lock up not in idle. if converter locks up in idle at a stop light the it may stall and make rpms jump. has this every stalled out on you? do you know where your tcc solenoid is and did you check power and ground to it? is the solenoid working as design? most time is a bad solenoid but also could just be a bad wire going to it. check the big trans wire connector and get a schematic for it to see if you have a bad wire or solenoid.