16-09-2023, 08:06 PM
If you haven't removed the dynamo yet, it can be tested as follows. Disconnect the "D" and "F" cables from the dynamo. Use an analogue voltmeter connected between "D and earth". Run the engine and you should get between 1 and 1 1/2 volts reading on the volt meter, this indicates that brushes and dynamo armature are good. Next connect the "D" and "F" terminals together with a short lead. With the voltmeter connected "D" to earth, run the engine, you should get approx' 7 1/2 volts reading on voltmeter. If you get these results, your dynamo is good. Reconnect "D" and "F" to dynamo. Next remove "D" and "F" leads from cut out, link the leads together, connect voltmeter "D" to earth , run engine. If you get 7 1/2 volts the "D" and "F" leads are sound, and the fault is in the cut out or SM5 switch. If you get no voltage for this test, there is a break in the "D" lead. If you get 1-1 1/2 volts, there is a break in the "F" lead.