Shift Solenoid help

So i have an auto 2000 gts. i know booo!!! auto but that's what i have to live with, any way my favorite light is on (the CEL) and I've narrowed down the problem. The manual mode is not working and I'm wondering if by the off chance any one else have had this problem. I'm fairly sure that the shift solenoid is the problem but which solenoid is it there are like 6 any one know the part number or the name of the actual solenoid that controls the manual mode. Thanks in advance. Oh and the code is p0773 in case you were wondering and can find more then i did.