weird lighting issues, HELP!

[Focusinprogress]

OK. so I've been working on hard-tailing my XS650 all winter. Before I tore the bike down, everything was in working order and the bike was ridden in stock form. I have just recently put the bike back together....and am having some strange wiring gremlins. harness is stock, I just de-loomed it and re-routed some things. I extended two wires, that's all I've changed.

so, I turn the key one click, neutral light is illuminated and the brake light is BLINKING. If I disconnect the brake light and the brake sensor/switch, the light stops blinking/shuts off. I have no power to my headlight on neither high beam nor low beam. If I unplug all of the headlight wires, tail light wires, and the brake sensors front and rear....this is what I get:

Green w/yellow tracer (front brake switch) has 5 volts
Brown (front brake switch) has 12 volts

Brown (rear brake switch) has 12 volts
Yellow(rear brake switch) has 5 volts

Yellow (rear light) has 5 volts
Blue (rear light) has 12V

Yellow (headlight) has no power
Yellow w/blk tracer (headlight switch) has no power

If I check the yellow and yellow w/blk tracer wires in the headlight bucket for continuity with the key "off" I get continuity. When I unplug the lighting saftey module, the continuity is gone.

I am at a total loss here on what's going on. If I plug everything in, the rear light illuminates but the front does not. I have also noticed that for some reason my bike does not have a fuse panel, just one in-line glass tube fuse of 20A from the power wire from the starter solenoid into the main harness.

This bike is a 1979 special.

I have a friends 1981 special here and if I test his yellow and yellow w/blk tracer wires for continuity, it does have continuity until the lighting safety module is disconnected (same thing as my bike is doing) and his bike runs/rides/functions normal.

What am I missing?

 

[Focusinprogress]

No one?

I've noticed that the plain yellow wire and the yellow w/blk tracer both originate from the same source, another solid yellow wire in the harness....they patch in right near the intake ports of the motor. Also, the Brown wire which comes from the ignition totally spider-webs all up and down the harness along the top frame tube.

I'm considering seeing if the bike will run, and if so I might divorce the lighting circuit and re-wire it to work without going through the "lighting safety module" unless doing so will prevent the rest of my lighting from working.

no one knows what witchcraft occurs within that "lighting safety module"???

 

[XSLeo]

Ok, your 79 Should have the 4 fuse box. If it doesn't then it has a harness from an earlier bike.
Most people that build a hardtailede bike rewire it so as to simplify the wiring.
On the stock 79 harness the safety relay does two things, it shuts off power to the starter and turns on power to the headlight. This started mid 78.
The reserve lighting unit works with the dimmer switch to turn on the high beam if the high beam blows out. This started in 77.
There is no lighting safety module.
The brown wire is the main power feed to most of the bike. It powers the brake light switches, tyurn signals, horn, regulator, Neutral light, most evrything that's head or tail light.
If you have a Clymers or Haynes manual they have wiring diagrams that show how the stock wiring is.
Your Reserve lighting unit may be bad.
What I suggest is rewiring the bike. I like this diagram. It starts with the basic points, seperate reg and rec. It has changes in boxes, If you want to change things, just swap boxes to match qwhat you have. It also shows the starter circuit in the upper right corner.
You can reuse the wires and connectors from your harness or buy new. Your choise there.
Leo

 

[Focusinprogress]

thanks for the help Leo! you cleared up a few things, and with about an hour's worth of chasing shorts and bad grounds I got the bike working like it should and even got her fired up for some crappy idling!