From 40oz Apps:
Super-duper simple app for looking up OBD-II codes. Simply enter the code (ex. P0300) and the app returns the description for that code. Used in conjunction with an inexpensive OBD-II code reader, you can find out what's wrong with your car when the check engine light goes on. (BTW...they sell OBD-II scanners that tell you the description of the code...and obviously you wouldn't need to buy this app.) Great for mechanics, or people who don't want to pay mechanics to find out why the check engine light is on.