Hello everyone. I just recently had a problem with my 2003 dodge neon sxt. The transmission was only engaging into reverse and 1st gear. I turned the key on off on off on off on and got a p0700 code. ok. fixed what it recomended and still did the same thing. After doing a bunch of unnecessary stuff i figured i would try to change the battery and now the car engages into all gears smoothly and now im getting the engine code of p0622 and relized it had nothing to do with input or output sensors, it was the altenator the whole time. This dose not mean that you are having the same problem but im just throwing it out there that it might be a possibility. apparently when the battery starts to drain you cant get the proper amps to run the system properly and can cause the transmission to only engage 1st gear. Hope this will help someone solve the same problem.

Ride on.
Jasmc051