P0700 is a generic PCM DTC that just informs you there is a DTC(s) in the TCM. Which, like Andrew said, could range from anything transmission related.
In other words P0700 is equivalent to seeing a check engine light for the engine, but not getting the specific code. You need to hook up a scanner to read the DTC in the TCM. Not sure if the key dance will work. Do you have the Superchips Flashpaq? I believe that can read TCM codes...