The connection to the neutral switch on my Valkyrie (GL1500-C) corroded and the light wouldn't come on unless I wiggled the wire. On my bike the connection is located beneath the right side timing belt cover.
The bike would start with the side stand up but the side stand kill switch would operate even with the transmission in neutral.
The GL1500 Gold Wing sometimes had trouble that originated with a relay in the the reverse switch circuit. I don't know the details.
