Join Date: Jun 2010
Location: Brewton, Alabama, USA
Year: 2000 & 1994
Model: 2000 GL1500SE Candy Spectra Red, 1994 GL1500SE Pearl Bermuda Green
It seems to me you have a poor ground connection. That ground wire from the side stand switch goes through a couple of connectors before it finds a ground to the frame. I think the most likely candidate is the C192 connector. It has a bunch of wires going into it from various circuits and they all have a common ground point. That connector is taped to the wiring harness on the left side by the fuel tank. It has been known to get resistance in the connector and cause poor grounds. I would try to find that connector and test it there.
Here is a link to a thread about that connector that another member found was causing problems for him.
Only two things are infinite... the universe and human stupidity; and I am not sure about the former.
-- Albert Einstein