Saturn VUE Engine Check light on No ODB code

The engine check ligh is on and I plugged in the OBD reader. No error code was displayed. What would cause this?

Thank you

What type of code reader was used? One would think that if the light is on that there should be some stored code. If this persists, take it to a good shop and have them attach a scanner instead of a simple code reader. The scanner is far more comprehensive in the data it can read out. you're welcome

Perhaps you didn't click the gas cap 3 times after filling? that's the #1 cause of the Check Engine light w/o codes.