Follow the white 3 wires from the stator assembly, 2 of the three wires take a right, the 3rd wire goes to the left. just after the left turn, the Diode symbol is there. Physically on the bike, its found wrapped in Tape in the bundle, (hidden, kinda) left seat rail, forward of the battery. you should notice some sort of clear see thou tubing. That is it, it is meant to be swappable with an OEM, however this part doesn't go bad with out some serious abuse. So double check it, Test should be in the manual, The Diodes let energy go one way, so the multimeter should allow the test tone to work one way, then swap the test leads the opositte, and try, it should fail. that is how the bike converts AC current to DC. The Diode prevents any return for the electrons.
I'm stumped. I have a jumper in the relay so the headlight should be getting power whenever the key is on. The volt meter reads +\- 13 V across the headlight plug, but as soon as I plug in the headlight bulb, the voltage goes to zero. Same thing if I have a battery charger on the battery or engine running. The battery charger hooked directly to the headlight bulb lights the bulb, so it works. All the other lights, horn, starter, turn signals etc. work fine. The mysterious diode is out of the loop with the jumper replacing the relay. This is an 81 400 xs II. Any ideas?
