What is the most common cause for the SES idiot light to come on. I dont have my OBD2 Cable for my PC yet so any ideas would help. My SES light came on 3 days ago, i reset the PCM and it turned off. Then last night it came back on when i was driving (Ironically in the same spot as last time). The light did not come on when i started my car this morning. It will probably come back again within the week. Any ideas ?

 

Any reply would be no more than a guess. That is not going to do you any good.