My SES light came on just b4 warranty expired. I brought it in to do tranny software reprogram and check the light. This was BMWs response on the invoice.

SERVICE ENGINE SOON LIGHT ON. SCANNED FOR FAULTS. FOUND GAS CAP FAULT. RAN TEST PLAN AND NO LEAK FOUND. FAULT CLEARED.

So the question is can I figure out what the problem is (in case its the same problem) or do I have to take it into the stealership for diagnosis of SES light? I assume that they would charge me some rediculous .5 hrs of labor just to scan it and tell me why its on.

Thanks in advance.