Funny you say that, that was my first guess, and I realise now what as happened, my boys were in the van playing the other day, and I bet they switched them on, however I have an extension cable running across the windscreen probably stopping the wipers moving even though they are swicthed on. Thus causing the burning out smell.
All makes sense now, if that's what they are, will check first thing tomorrow when I can see what I'm doing lol
Thank you very much for your insight, much appreciated.
Paul