I just thought I’d throw this out there as a “service bulletin” for anyone interested. I took a bike in recently for work because the fuel pump would not prime. I suspected the pump was fine, everything else on the bike was in working order and the bike was intermittently shutting down while out on the road. 35k miles on the odometer, all the simple checks came back fine – relays in working order, kill switch functions, etc, etc, etc… What struck me as odd was that you should always get battery voltage (~12V) at the engine stop relay, even with the key off. I was reading battery voltage there with the key off, but when I turned the key on this voltage dropped to roughly 1.5V. I figured I had either a serious draw/short somewhere that wasn’t tripping fuses, or something like what I found…
Under the left side cover you have your main battery cable that feeds your 2 main 30A fuses. The wiring from those 2 main fuses then runs through a simple 2 pin plug before running over to the keyed ignition and so on. The plug looked almost perfect upon a cursory inspection, but when I went to separate the plug is when it got interesting:
This was the source of the problem on the bike and unfortunately it was caught too late to save the plug and some of the wiring. I had to replace several inches of wire and add a whole new plug. This was simply a matter of corrosion buildup on the connectors over time and could have been avoided with a little contact cleaner to clean up the contact areas. It won’t hurt to separate this plug, clean the contacts and then pack them with a little dielectric grease to prevent further corrosion (just don’t go overboard with the grease).