The check engine light can come on for many different reasons. Most sections of the vehicle are monitored by thge computer system in the vehicle. When the computer sees a problem it registers a fault code in the computer memory and turns on the check engine light. These fault codes offer a generic description of the fault but do not tell you the exact part that caused failure. An example of a fault code would be P0456 small evap leak detected. As you can see this computer fault code tells you that there is currently a leak in the evaportive emissions system but does not tell you where in that system the leak has occured. We can pull the fault code any time free of charge but in order to properly determine the part failure we recommend to have our ASE technicians perform an engine computer diagnosis. This diagnositc will tell you exactly what part failed and what its going to take to resolve the fault code.