Headlight Question

[Dux]

Thanks so much for the detailed response, Scott. I really appreciate it!

[QUOTE=3Phase;444209]How's it going, Dux? Do you have a manual and/or a schematic?

1980 XS1100SG/LG and 1981 XS1100SH/LH Color Schematic

Yes, but not color. Thats awesome! Thanks


With the Ignition Switch OFF and the Engine OFF:

Check the Battery voltage and make sure it's greater than 12.6 volts.

12.65v

With the Ignition Switch ON and the Engine OFF:

Check the Battery voltage again to make sure it's still greater than 12.6 volts and not dropping too quickly with the basic pre-start electrical load.


12.2v (jumper = Headlight is on when switch is on)

Check the voltage on ALL of the Brown wires at the Input/Line side of the Fuse Block. The Brown wires are the 12 volt switched power feed from the Brown wire at the Ignition Switch. They're all spliced onto the Brown wire inside the wiring harness just upstream of the Fuse Block so they should ALL be within a half a volt of the Battery voltage.

and here is where i think the problem starts, i'm getting 11.1v on all the brown wires at the fuse block

I'll work through the rest of your tips... (btw i recently installed the new style fuse block)
Thanks again,

[natemoen]

Now you need to go check the voltages on all three of the wires at the back side of the ignition switch and report back. They should all read the same as the battery with the key on, engine off.

[Poprock]

Bypass the RLU. Necessary for any lower-draw headlight. Clean all connections on the bike. Fill with dielectric grease. Clean grounds everywhere. Helps everything work better. Learned that from the Geezer.

[3Phase]

Resized 1980-81 US headlight relay sub-schematic

I resized the tiny 0.7x2 headlight GIF so it's easier to see, then converted it to a PNG.

The image you see here is the new 2x9 PNG file and you can save it but Flickr frowns on just direct linking to their server so here's the Share link too. Because there may be someone, somewhere, that can't use PNG files there is also a 2x9 GIF at my Flickr page. :-

------>

1980-81 XS1100 USA Headlight Relay (2x6) PNG
by Scott_Ci, on Flickr


1980 and 1981 Yamaha XS1100 USA Headlight Relay and wiring harness connector diagram.

Models:
1980 XS1100 G Standard, SG Special, LG Midnight Special.
1981 XS1100 H Standard/Venturer, SH Special, LH Midnight Special.

Clockwise from the lower left:

Black = relay coil ground
White = relay coil input half-wave rectified 12V DC from one phase of the alternator stator
Blue/Black = +12V DC 10A output to the RLU (Reserve Lighting Device)
Red/Yellow = +12V DC 10A input from the Headlight fuse


.

[motoman]

and here is where i think the problem starts, i'm getting 11.1v on all the brown wires at the fuse block

Ignition switch and kill switch contacts is likely where the 'missing smoke' is located Same identical scenario, and with 3Phase's litteral hands on help a couple yrs. back, all is good.