Jeep Repair: auto trans wont shift, backyard mechanic, jeep xj

Question
I have a '97 jeep xj with the 4.0L and the aisin 4spd auto trans. This past Sat. after driving about 7 miles, the tranny downshifted when I was going up a hill, but once over the hill, it was "stuck in 1st gear". I limped it back home, checked the fluid.. OK.. let it cool down, and tried it out again. Same thing, won't shift out of 1st even with high rpm's. I disconnected the battery, let it sit, and re-tried... same thing. I am a good backyard mechanic, and I can't afford to have a "re-build". Are there a few things that I can do (I am capable of pulling the tranny out)prior to taking it to a shop?

Answer
first of all u dont ever want to rebuild that tranny  it will cost more then putting a unit in there. With out knowing what the codes were b4 u erased the battery  u might not know   U will need to have a shop hook it up to the tranny computer and hope there is a code in there.