Chrysler Repair: 95 New Yorker transmission limp mode, transmission controller, relay circuit

Question
Tranny was slipping, friend told me to add gunk. Tranny went into limp mode. I checked codes and came up with 77 (speed control relay circuit). Should I replace fluid and where is this circuit?  

Answer
Hi Dave,
The code you got (probably via the check engine light?) is related to the cruise control not the transmission. If you want to get the transmission fault codes you need to get it from the data link connector that is under the dash by the steering column and using a code reader that can access the transmission controller. So do that first, let me know the code number(s) and then let's go from there.
Roland