Not sure if that scanner can do the TCM. Don't fret about it until you get a code. I would say it's a very good chance it's a sensor if the fluid is clean and has been changed regularly. Chrysler set up the transmission so that if the TCM gets confused, it defaults to a state where it can't hurt anything by giving bad commands. The speed sensors in particular seem to fail, IIRC there is an input and an output.
EDIT:
Clicked the link, and that scanner almost certainly cannot do Chrysler TCM codes, at least on your vehicle. OBD-II wasn't used on any of the K-based cars, the electronics just aren't sophisticated enough. The interface is also physically different, the TCM communicates with the scanner via a 6-or 8-pin plug.
