Sudden irratic trans shifting

My trans began shifting irratic VERY suddenly. I have taken it to Lincoln dealer and they replaced the shift solenoid. The problem is better (it doesn't jerk ALOT anymore) but still has this shift pattern :
Instead of 1st,2nd primary, 2nd lockup, 3rd primary, 3rd lockup and then into overdrive......
It is: 1st, 2nd lockup, 3rd lockup and, overdrive.
This pattern is now very consistent (better with new solenoid).
I believe it is electrical, something making converter stay in lockup. The application of the brake pedal does not take it out of lockup, valve body and trans mechanical checked very thorough (no excessive wear indications, pressures good, ((47,000 miles by the way)).

Does anyone have info on where to look for an electrical fault?

I replied to your inquiry on the
www.markviii.org board.

seriously....check into what I wrote. I am 90% sure about the answer.

if not, try
www.flatratetech.com

First thing to do is find someone who can scan it......it should tell you your problem right away. Save you some money.