lights working in coach with battery So switch off

It would appear that a previous owner has wired the lighting in by going around the disconnect solenoid and wiring direct to the battery. You will just need to do some investigation to find where they tied in and move it back to the dead side of the solenoid.

If you have a small switch panel where you enter the RV that has a porch light switch and the battery disconnect switch, I would suspect that to be a likely spot to pick up direct battery power from the hot side of the disconnect switch.