I have a St 3 focus and it just dies at random times it can go days being fine then it can cut out all electrics ate totally dead no power for hazards anything then all of a sudden it will come to life and start ???

Any help please apart from my first thought petrol and lighter

 

Have you had the recall done affecting the wiring harness? It was a recall here in the US. Probably affects your 62, 13, and 63 plate cars.