81 XJ550 maxim, Headlight and gauge lights out

First I'd like to introduce myself, my names Gary I'm from Michigan been lurking here for a while and decided to join. I ride an 81 550 pretty much original except drag bars.

ok here's the problem last night while riding home my head light and gauge lights went out, they came back on a couple times then shut off for good. everything else still works neutral light turn signals tail brake etc. I pulled the relay and I'm only getting 6.7V to the relay at idle when I rev it it jumps to 11V. at idle the relay vibrates like the voltage is to low but even when I pulled it apart and held the contacts closed with the bike running the lights did not come on. I thought maybe it had a bad ground but the ground for the relay is good and I assume the ground for the light is good since I read 1.2ohms though that circuit from the relay harness. any ideas would be GREATLY appreciated. Thanks Gary

 

have you tested the battery? is there any problems with getting the full voltage just out of it? without knowing much about these bikes i'll say one thing. ive heard that sometimes the wiring goes under the gas tank and can cause shorts. don't quote me on it.
anyways hope that helps

 

I would check your fusebox. The wiring is pretty horrible under there, and often causes lots of problems. Replacing mine fixed a lot of weird electrical gremlins/issues on my '82 650.

 

also check your headlight relay - it controls the headlights and guage back lights. the contacts on mine were completely varnished, sanding off the pins and cleaning the plug with contact cleaner did the trick.

 

the headlight relay is under the gas tank, its the small cube shaped one with 2 pins

 

thanks for the responses. I checked everything again and couldnt find the problem so I went back to the fuse box and upon closer inspection sure enough the headlight fuse was blown, the metal strip was still intact but the end had a hole melted through it.