Headlight not working, voltage OK


XS650 Addict
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San Diego, CA
Hi everyone,
Looking for some pointers - my headlight will not turn on.
I checked the voltages: 12V at the green with 0V on yellow on low beam, 12V on the yellow and 1V on green with high beam, and the ground is good (about zero ohms between ground plug and frame).

I put in a new bulb and nothing happens. Bike starts up and runs fine, blinkers work, horn works, no other problems...:wtf:

Thanks for your help!
You maybe getting 12 volts on those wires but weak connections or dirty contacts in the switches can add enough resistance to the circuits that not enough current is flowing.
Try checking every connection in the circuits to see if any are bad. Pull the switches apart and clean them.
Thanks for the tips guys.

Brassneck: Yes, I actually have 12V going to the socket but no light.

The socket may not be getting enough current, as XSLeo suggested (Thanks Leo). To test this, I connected the high beam from the socket to a brown wire, started the bike and the light turned right on.

OR, the Reserve Lighting Unit has failed - thanks for the link 5twins.

5twins: Yes I still have the RLU. Can I really just unplug and toss it?

Read that link. You need to jumper two wires together. But essentially, yes, you can get rid of the thing. Along with removing the RLU, you can do another simple little mod at the same time to give yourself a charge indicating warning light, like the "Gen" light on your car's dash .....

5twins nailed it. After bypassing the RLU the headlight works great (high and low). Anyone want an RLU? :laugh:

Thanks for the help & Safe travels..