The best thing to do is to go to someplace like AutoZone and they will check for codes for you tell you what they are and clear them out at no charge to you. If you don't have an AutoZone near you or you perfer to do it yuor self you can disconnect the battery cable for about10 minutes and that should clear your computer. Make sure that if you have a radio that needs a security code that you have it before disconnecting the battery.
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