engine light will never come on until you cruise the truck at 55 or 60 miles an hour for about 5 miles. it will go off when you slow down to stop and stay off until you take it back up to 55 or 60 hard to code it while driving 55. anyone ever experience this????

 

I dont think you need to have the trouble sensor lit to check for OBD codes. there should be a write up on trouble codes and how to read them without an OBD if thats possible on your vehicle.