Dodge Repair: tranny in limp mode, dodge dynasty, output speed

Question
Hi Doug. I wrote you once already about my relay but I forgot to ask you this too.  RECAP-1993 Dodge Dynasty LE, 3.3 engine, a Mopar tranny (with overdrive) either a 440 or 660 (from what the mechanic tells me). My tranny won't shift from 2nd to 3rd.  I took it to a tranny shop and they said it was in Limp mode (to my understanding limp mode is what the tranny goes into when something mechanical goes wrong inside the tranny and it's like a donut for a tire, can't drive 100mph but it'll get you to A and B without burning out the tranny). I asked him if he ran a diagnostic on it, he said yes, I asked him for the code, he said no code comes up on the diagnostic? Then he tells me that I need a turbine sensor, so I buy the sensor, put it in and all it does is fix my speedometer not the tranny.  I'm lost.  I don't want to get got from a shop, if you know what I mean.  Any suggestions?......

Answer
Well, it's an electronic transmission with alot of problems that can materialize and throw it in to limp mode.  The "Turbine" sensor he replaced was the output speed sensor.  You've also got an input speed sensor that looks almost identical.  If he replaced the wrong one, if he didn't clear the Trans controller memory or he just plain mis-diagnosed the problem then any one of those conditions could be the cause of the vehicle still being in limp mode (which is that point A to point B, second gear only mode).
Doug