That's what I meant when I said the next customer may not be so lucky. If there IS an L to E fault, the RCD should trip if it is working. If it's not working there's a good chance the MCB will trip.Unless there is a L to E earth fault in the van
If the earth is missing, and there's an L to E fault, the whole van becomes live, and there's a real possibility of a lethal electric shock.