If all fails before taking it to the dealer you may want to try to clear all the DTCs. If you have a aftermarket performance device such as Z Automotive Tazer you can do it using that device. If, not you can try going to AutoZone or Advance Auto and have them do it. Not sure if just removing the ground from the battery will do. Can't hurt to try it though. The dealer will charge you $125 or better to perform a diagnostic.