I recently changed the ECU on my car. The new ECU has been reprogrammed to my engine tune. The problem I have now is that the transmission will not shift into overdrive most of the time. The way I can get it to work sometimes is to restart the car. What I have found is that the ECU is showing engine codes C0237 and C0240. I can't figure out why i get these codes and how to get rid of them.