For the past couple months I keep getting an 0505 (clear) code from my SES light. I reset it, but it comes back on within the day. It seems to be a couple seconds after I start the car. I know it could be an electrical problem, but I have no idea where to start with this one. I have a new battery, I've grounded the hell out of my car, and my sound system is grounded. Where do I start?