Hi heidy, the simple answer is I did not fix it, although I did find that next to the battery is a "Brain" that has some wires going in, I found that when it was not starting if I mashed this area with the palm of my hand the blighter would start to behave for a few days (bad connection I suspect) I would not reccomend that you do this however as it may invalidate and warranty you have ! (best get a mechanic to do it).
My megaine went back and I got a new Ford Focus instaed and I'm much happier with it than I ever was with the renault (I'll be sticking with Ford from now)
Porl
January 2010