The Chrysler TCM doesn't pass many codes at all thru the OBDII protocol port or PCM. Maybe one or two codes, probably from the PCM that it sets itself from talking with the TCM.
The Autozone Reader is a simple OBDII reader, it does NOT communicate with TCM's, Body Computer's, ABS Modules or Air Bag Modules. He may have to take it to a dealer or repair shop with the extremely expensive scan tools, that can read the TCM.
Give it a try, I could be wrong.
As well, I "THINK" the Chrysler 42RE is just the A-604/41TE trans adapted to RWD. That trans typically locks into "Limp Home" mode when it encounters a serious problem. It locks the trans in 2nd Gear, which 2nd Gear could seem like 1st when your used to a 4spd auto. Usually the problem is bad enough, that the only fix is a rebuild.
I made a lot of guess's and jumps in logic there, for your friends sake I hope I'm wrong and its a simple problem. It can't hurt to stop at autozone and have them scan, but I think your going to have to hit a dealer or transmission shop. Expect they may tell you that it needs a rebuild, and you want to get a 2nd or 3rd opinion and price qoute on that. Many trans shops rip people off, as well as dealerships.
