I am having intermittent problems with starting my motorhome. Sometimes when I turn the switch on, it starts immediately. Sometimes it doesn't and requires several twists (3-20) of the key before it fires. I don't see the dash voltmeter going down as I would expect if the starter is binding. It just doesn't do anything. I have tried moving the shift lever, but have have not noticed any improvement. So far it has eventually started, but someday it might not.
My first thought is to put a voltmeter on the starter and see what happens when I turn the key...this will require really long arms or an assistant.
Any ideas on how to check the ignition switch itself? Anything else to check?