If you put a meter in across the battery and +feed to the car, what are you doing exactly?

A volt meter across the battery +6V and -0V will read 7V or so.

A volt meter across the battery -0V and the "B" or "A" terminal of the switch panel will read 7V or so (irrespective of switch position).

Terminal "A" is also connected to the cut out. If the contacts of the cut out are closed, then current will flow into "D+" of the dynamo. But this should not be a short circuit but you will be heating the dynamo.

If both switches are in the OFF position and the cut out is open, then no current should pass as the other terminals on the back of the switch panel are not live.

Is there a large discharge registered on the ammeter?

- No? the short is occurring on the way to the switch panel (perhaps the "B" terminal is shorted to the dashboard?)

- Yes? the short is occurring after the ammeter, but before lights, coil, horn (perhaps the A terminal is shorted to the dashboard or cut out is short).

Hope this helps

Peter


ETA - following from a previous post - another failure is that the split pin that holds the switch knobs on can short against the face of the switch panel (but usually only when the switch panel is screwed in to the dashboard).

Hi Peter
Wow - thank you for all this knowledge. I will check these things tonight/tomorrow and let you know how things stack-up
regards
Adam

Location: london