Left ballast issues

[towermounts]

I'm having issues with my left(port) ballast pump turning on every time I start my boat. It will turn on even if the tank is full. Im wondering if it's a electrical or B.I.G. System issue. I had a dealer look at it and They said they found a corroded connection and said that was the problem. It still happens but it will stop if I disconect the battery's but after about two engine starts it starts to act up again. Anyone know how to fix this?

2010 X-2,with big system