A friend broke down today, basically the lights would come on the dash but it just would not crank, not clicking no attempt at the starter kicking in.
He had a go at checking things but could not see any thing obvious so he called the AA, he checked the battery first, then put a jump cable negative lead on the negative pole, and the other end on the chassis and it fired up and said straight away it was a broken or damaged earth somewhere but couldn't say where as he said theres about 15 earths on a mk4 golf and made a temporary earth to get him home which it did.
I'm guessing what he did created a earth with the jump cable, nice trick that I'll remember that.
Any ideas where would be a good place to look for engine earths to see which one is offending.