Our trucks aren't OBDII compliant due to their GVWR, I promise you if there was a SES or CEL light you have a stored code. But those generic readers won't read our trucks unless they have the Superduty software loaded and the stores won't pay for this. You must go to a dealer of find someone with a reader that will work. If you look on Ebay for a old 1705 Superchips programmer for our trucks you can find them for $100-$150 I wouldn't use it's tunes, but it makes a good code reader. You may want to post your location and say your in need of someone to read your codes. Maybe some other member lives close to you.