Headlight issue

[djdesantis]

I am seeking some help on getting my headlight to work on a 94 Wombat. I have built up a bike and I had Greg Watkins build up a magnito for me. I have finished assembly and have a great running bike with one issue. The Headlight will not work. However the headlight works on DC mode, both hi and lo beams. But on AC mode it will not light, nor will the tail light. I have checked all wires in the headlight circuit and they are sound and making connection from end to end. My thoughts are telling me to check the source of the voltage from the mag, to the switch and then on to the emergency switch. Based on the wiring diagram, what leads from the mag make the connection to the ignition switch and on to the the green wire going to the emergency switch? I wanted to bypass the ignition switch and see if this is the issue. It should be simple to troubleshoot but I can not figure it out. I can not determine what lead from the mag to the switch actually powers the headlight. All other electrics work fine. Thanks! Are all of the ignition switches the same from Ace 100 on.

[thrownchain]

I fail to see the issue, you have lights that work. What's the plus for getting them to work on AC?

[djdesantis]

Isn't my battery going to drain? I beginning to think either the lighting coils are not up to speed or the ignition switch (new) is defective. I am going to start the bike without the ig switch, just run grounds from the blue leads off the mag and pull the volts off the mag leads, the green and the yellow and see what I get. The green is the low beam lighting coil lead and the yellow is the high bean lighting coil lead.

[rlkarren]

No, yellow is the output of 1 coil (~22w), green is the output of two coils (~45w). Hi/low is determined by the handlebar switch and nothing else.

Green is the circuit that powers everything, but only when the key switch is in the 2nd position.

There are so many variables that it’s really prohibitive to diagnose without being there. You have to use the process of elimination to find the issue. Is the magneto outputting power on the yellow and green leads? Is power coming out of the key switch on yellow with key in Position 1? Likewise with green in position 2? Is power reaching the headlight leads when key is in position 2? (there should not be power on green with key in position 1). Is power making it to the emergency switch? Etc.

Honestly, you have to study the diagram and check for power at every junction/switch along the path that power should follow to the headlight. Just remember that the key must be in position 2 to test the headlight. And you must must must have a VR installed on the green wire from the key switch or you will likely blow the bulb on rev. I know, I really hate “RTFM” answers, and I’m sorry that’s all I can offer, but in this case there really is no other way without hands on.

Good luck. It’s going to be a bad connection or a bad emergency switch or key switch.

$0.02

Roger

**EDIT** I wrote everything above from memory. I need to make one correction to the statement in italics above. It should read: Is power coming out of the key switch on white with key in Position 1?

Magneto -> yellow -> keyswitch (position1) -> white -> rectifier -> red -> battery+
Magneto -> green -> keyswitch (position2) -> green -> Emergency switch -> brown -> Handlebar Hi/Lo switch -> yellow -> Headlight Hi (Light Blue ->Headlight Lo).

[gregg_floren]

It's been a LONG time since I messed with the emergency lighting switch (and I could be wrong here), but as I recall the emergency switch is not set up to power the headlight. It does power all the other lights like the tail, brake, and speedometer.

And for exactly the reason mentioned. It would drain the battery in no time.

Gregg

[Dale]

For clarification, the emergency switch provides "emergency" headlamp operation by switching to DC operation. This is not the desired operation for normal use as charging of the battery can not keep up with the drain. You want the switch on the AC postion.
Secondly, you can take whatever Roger advises to the bank. He's my hero when it comes to Hodaka circuitry.

[Bullfrog]

I'm with Dale . . . follow what Roger said.

I would add one little item which is easy to miss - check to be sure that the "plate" of the rectifier has not rotated such that a corner is touching metal. Don't ask how I know about that little item.
Ed

[djdesantis]

Thank you for all of the advice. I dig learning all of his stuff. So I unplugged the switch from the mag leads, I cut the harness off an old, non working switch to the mag lead so I would have the four wires to attach test leads to , the black, green, yellow and blue. I attached the blue to ground and left the other three hanging free. I started the bike and tested the remaining leads. Black was good, already proven because he bike runs, green was putting out a trace of voltage and the yellow was putting out 0. So the coils are bad. Sending it back to Greg for repair. All will work as it should when I reinstall it. Based on what I learned, I am going to build my own wiring harness for my next project, another Wombat I am building up. Cheers!