No power tp headlights or light switch but all harnesses and fuses o.k.

Frustrating one.

I cleaned up the front headlamp frame, turn signal wiring and tested, all o.k
Then, I rolled it out to be cleaned and although the bike starts, markers work, turns work, the headlamp will not work in high or low.
So, I-checked fuses with a 12v tester and they are good. (I checked for 12v on either ear).
Checked and sprayed the harnesses and they all seem clean and tight.
Swapped headlamps and also an old harness I had and no change.

I am trying to follow the wiring diagrams. It seems I am not getting 12v at the light switch, and when I follow the wiring to the harness and larger switch, the connections seem o.k with a meter.

I can't figure out where to go from here?

Thanks in advance.

 

You didn't specify what bike, but since you're posting in the 1st/2nd Gen forum I'll assume it is from that era.

The starter switch and button are a fragile design on the early models. See if the starter button wants to be pulled back out a little or if it's cocked to one side. The switch kills the headlight when engaging the starter with the button, but can get stuck in between functions. Also try spraying a little WD40 into the starter button area.

I've had to replace quite a few old style switches on my 1st Gens due to the fragile button design. Just did it on one of my 1000R when it just wouldn't let the headlight operate anymore and I had to "pull" the start button out with my thumb after starting.

Here is the switch with the broken button stuck in and cocked to the side a bit.



https://vfrworld.com/threads/1985-vf1000r-getting-close.37749/page-4

 

Sorry, it's an 84. I did have to repair the starter switch once and maybe it's failing again. The button stuck slightly due to overheated/warped plastics. I'll check it again. Thanks.

 

Manipulate and wiggle the button around and see if the headlight wants to respond. I'll bet that's it if you have already had problems.

 

As I was reading this I thought it sounded familiar. It's the exact same issue I chased for a few weeks before you told me to just wiggle that starter switch (pulling it back a bit after starting).