Hyundai Repair: Overdrive problems, transmission control module, gear overdrive

Question
Hi,
 I have a 2002 hyundai Accent.The car drives fine with the overdrive off but when I engage the overdrive it seems like the transmission cant make up its mind whether to stay in overdrive or not.I had the codes pulled from the computer and they are P0734 and P1529.Do you have any idea what they mean or what is going on with my transmission?
    Thanks,
       Jeff

Answer
If your fluid is at the proper level, I have bad news only.  You'll need a transmission overhaul or replacement.

P0734 indicates your transmission is slipping in fourth gear (overdrive).  P1529 indicates the transmission control module (TCM) sent a request to the engine control module (ECM) to turn on the check engine lamp.