How can I fix short in Rowenta "Professional" model Iron?

I love our Rowenta Iron - it seems to be shorting out. Problem seems to be where cord connects to iron. It has a "rotating" ball where cord meets iron. The iron shuts off when I move the cord at that location. Would like to know if there is a tool that will fit the screws on back plate. A Phillips screwdriver will not do the job. I'm sure we could just tighten the loose wire if we could get plate off back of iron. Thanks.