Headlight problems on 84 VF500F - stumped big time

Hello All,
I am new to motorcycling and recently bought my first bike - VF500F. I have ridden it sporadically for the past two months. Great fun :biggrin:
Now I have a problem.....From one day to next, the headlight stopped functioning (nothing - no LO, no HI). I checked every posting I could find and have looked at everything I could for 3 nights now to no avail. Things checked:fuse,Hi-Lo rocker switch, starter switch,changed bulb.
I have noticed that when I put a voltmeter on, I have power (12.8 volts steady) on the white wire, none on green and none on blue. I am guessing that the green is the ground.
When on Hi, there is no juice on the white wire. There is no juice on the blue in either position.
Before taking everything apart, I thought I had lights on the oil, neutral, but no light on the high in the console. Now I have no lights at all for oil, neutral and of course high.
Does anyone have any suggestions??

TIA,

William

 

Initially it sounds like grounding problem. Follow the green wire and check for continuity. Also the connector is a suspect.
Secondly there is an issue with hi/low beam, I would also start with cable continuity before going to rocker switch.
Hope it helps.

 

I have checked for continuity on the green wire, it seems OK. I have checked the blue wire as well - but can't seem to find exactly where it branches off - if I follow the wiring diagram, power is supplied to the blue wire at the Hi-Lo switch. I am assuming that these HB4 bulbs require current accross two terminals at a time - what I can't figure out is at the connector there is 12 volts coming out on the white wire and it seems the green is ground properly. I have also tried connecting another wire from green to ground - no joy. Should I not be getting at least low beams with 12 volts on white??

 

Let's then start from basics. Is lamp ok? It only needs +12 volts and ground to work, if they are both present at lamp's terminals it should work.

 

I am such a doofus! Just spent 6 hours going through every wire that leads to the headlight with voltmeter. Finally got fed up and attached the bulb to two wires and started working back.
Got to fusebox - and on the other side - got a light ....checked fuse with ohmmeter and - no continuity accross fuse!!!!! checked spare that was in the fusebox - and no go either.
Change the fuse and reseat everything from R/R towards front and voila!!
Other than the fact that I should always check fuses with a meter, what kills me is - why was I still getting 12V on the white wire at the connector???
I also found a frayed throttle cable when I took the starter switch apart - so I guess not a total waste of time..

Thanks for your input blitzas.

W

 

Welcome! :canada:

glad you found the problem. Won't be the only one with these bikes. :banana:

 

I suppose your readings were at connector with lamp removed. If it was like that "normal reading of 12 volts" has to do with the high input resistance of the Digital Multi Meter. Your fuse was not totally open, it had a resistance which was fine to give a 12 volts at DMM but it is also very restrictive in supplying the lamp with current.
Believe it or not the best instrument when it comes to automotive continuity problems is a 5W lamp tester!