HI, I've got a 2004 Chrysler Concorde 2.7l v6 around 123,000 miles with a transmission issue. Any help diagnosing this would be greatly appreciated. Unfortunately I don't have a scanner.

Car starts fine but once driven for a while and above 3rd gear when downshifting it will get stuck in second gear and the only way to get it unstuck is to pull over turn off and then turn it back on and then it's fine for a little while until it reoccurs.

 

do the on key of trick it will display the codes then can go from there