single headlamp lo beam issue

[Chengaskhan]

Hi all,

I’m a noob to working on motorcycles and the electrical system. I purchased this bike with the 7” round single headlamp conversion already done. The headlights low beam was intermittently flickering and eventually died. I changed the bulb and checked the fuse. The wiring harness looks fine. In the red boxed area, the blue wire was loose. Don’t know which of the two connectors it went into. But looking at the length I guessed it belonged with the black wire and recrimped onto a new connector.

The high beam wiring is 1 wire to each connector, but the lo beam side has 3 wires. Why is that? Does anyone know how I should rewire this and what is causing the headlamp not to work?

-Thanks,
Alan

 

[Motogiro]

:welcome:to this awesome forum!

A common occurrence when people are having trouble with the headlamps on the FZ6 is they may forget the the headlamp circuit does not activate until the engine has been started. Make sure you have started the engine and then you can stop the engine with the emergency kill switch and the headlamp circuit should stay active for troubleshooting until you turn the ignition key to the off position, Don't forget to turn the key off.

Your head lamp looks like it has the H4 bulb. There are 3 wires attached to the H4 plug. One wire is the hi beam. One wire is the lo beam and one wire is the ground. The ground is used as the return path for both the high beam and the low beam.

The H4 bulb is a dual filament bulb this means that there is one glass envelope and within that single glass envelope there are 2 very hot burning halogen filaments. Only one filament inside the that H4 lamp should be on at a time. This means when the low beam filament is on the hi beam filament should be off and when the hi beam filament is on the lo beam filament should be off. The original wiring for the FZ6 built for the US. market had a fairing and 2 separate left and right headlamps. One headlamp was for the low beam and one headlamp was a hi beam. The hi beam lamp was the H4 type and had 2 filaments but only used the hi beam filament. This made the bike look like on headlamp was out all the time so people wanted to use the unused low beam filament. There were a few bike manufacturers that did this. Because hi and low beam function were in separate lamps there was no need to shut off the lo beam on one side of the bike when the hi beam was activated because of the separate bulbs.
If your lo beam does not turn off when the hi beam is turned on the lamp will overheat and be damaged and/or fail prematurely. There are ways to make it operate properly but first make sure the lo beam and hi beam are both active. You can do this using a 12 vdc test light or a multimeter. One wire on that H4 plug is the ground. The ground wire is a plain black wire. The lo beam wire color is black with a green tracer. The hi beam wire color is black with a yellow tracer. Remember when the hi beam has voltage there should be no voltage on the lo beam wire.
Do these tests first and then post your findings.

 

[Motogiro]

Also the wires you have in your hand (red square) look like there is a black wire attached to a blue wire. If it is a plain black wire it is a ground return and should not be attached to the blue wire. I think the wiring you have in your hand is the turn/4 way indicator wires Those wires will operate the left and right side indicators. The color code for those will be brown and green.
Here's some more info on color code.

Left front turn signal with running light. That's two filament per bulb in the front.
Chocolate colored wire= turn signal filament.
Blue with a red tracer colored wire= running light filament.
Black wire= Ground or negative.

Right front turn signal with running light.
Dark green colored wire= turn signal filament.
Blue colored wire= running light filament.
Black wire= Ground or negative.

Left rear turn signal.
Chocolate colored wire= turn signal filament.
Black wire= Ground or negative.

Right rear turn signal.
Dark green colored wire= turn signal filament.
Black wire= Ground or negative.

 

[Motogiro]

Here is the H4 plug configuration looking at it from the back.

 

[FinalImpact]

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