Damn, there's a few of you lately with this problem..
There are a TON of electronics on your car and if you are "faint hearted" or are wiring challenged - take it to the dealer. If not then check the following - check all your grounds - ALL of them - you'll find ground bundles everywhere. Next check connectors to OBC, and others like it under the dash. (It could be as simple as a loose connector or something worse like moisture or corrosion in a connector. Check the socket where Oil reset & inspection resets are done. There's alot of you guys out there that are running around without the cap on it - and that is taboo.) This should get you started, you might also want to invest into a bentley manual with wiring diagrams, a volt/ohm meter and a test lamp. Happy hunting.