I just changed both batteries in my 03 and now the check engine light is on and ideas on the the reason please help new to the durmax here

Do you have tuner that reads the engine light codes. If you do there are guys here that will tell you what that code is telling you. If you don't have a tuner I think Wal-mart or Autozone if you are near one of them they will test and tell you what the code means for free. It shouldn't be anything major.

The check engine light will come on when you replace your batts. This happened to me. Drive it around and it should go away soon. The problem code is probably just your computer thinking it hasn't received enough electrical juice. STAGE 2 W/CO PILOT AND 5 STAR GET IT TODAY FROM SHOP!!!