My kill switch doesn't work for some reason and as My knowledge on anything electrical is about zero I was wondering if it needs to be working to pass scrutineering? I can imagine the marshall's getting pretty cheesed off if I came off and the kill switch didn't work. There is a ignition on/off switch but its not as obvious as the kill switch.
As Paul says it is a requirement of the ACU regs that you have a working kill switch of some form on the handlebars. Also handy when you stop rolling after a crash as you can hopefully get to your feet walk over to your bike and turn it off just as I did with mine at Snetterton last year