No power to headlight

Hello, I’m working on a 1975 z1 basket case. Started with just a frame and basically built a z1 from the mail 😆. Anyway, Im installing a brand new wire harness. The headlight is new as is everything. I couldn’t find an oem headlight but bought a cheapo  sealed beam with 3 wires: green, blue and white (I assume this is ground?) I’ve connected the blue to red/yellow, green to red/black and white to black yellow. Headlight doesn’t work, however when I press the “passing” button on the controls, the light comes on. I know the light works because I tested it on a battery, tail and break lights work fine. I only see one fuse for the entire harness… I find that strange. A any suggestions? Thank you in advance !

When you press the "pass" button does the high beam warning light come on and does the the high beam come on full brightness ?

Yes the high beam warning light goes on in the instrument panel when I press PASS. It appears to be full strength (I dont have one of those 'pub lights')

danam wrote:

Yes the high beam warning light goes on in the instrument panel when I press PASS. It appears to be full strength (I dont have one of those 'pub lights')

does your right handlebar switch have "PO" and an "ON" position ?
Are your handlebar switches "OE" or after market and do the colours match the new harness ?
Also I suspect the white and green are the wrong way round (doesn't explain why the lamp works on "pass" but not "high beam")
If it's a sealed beam does the OE plug not fit straight onto it (pictures would be helpful
Do you have a voltmeter ?

Everything is aftermarket, the controls an harness all resemble oem, same color wiress controls plug in correctly. I had to put my own connectors on the headlight as there were no e but they are high quality Wirefy Inc) I tried swapping the headlight wires around with no change. I have a multimeter, right control has ON-PO-OFF

 

danam wrote:

Everything is aftermarket, the controls an harness all resemble oem, same color wiress controls plug in correctly. I had to put my own connectors on the headlight as there were no e but they are high quality Wirefy Inc) I tried swapping the headlight wires around with no change. I have a multimeter, right control has ON-PO-OFF


 

how many wires coming from the left handlebar switch and how many in the loom ? (according to the wiring diagram the "pass" button is European spec and the loom has 2 additional wires over the US spec

danam wrote:

I couldn’t find an oem headlight but bought a cheapo  sealed beam with 3 wires: green, blue and white (I assume this is ground?) I’ve connected the blue to red/yellow, green to red/black and white to black yellow. 

Your best course of action is to identify what the wires in the headlight actually do, rather than connecting them at random to see what happens.

To answer Nerd’s suggestion: I connected the headlight to a battery green and blue are hi/low beam, white is ground. 


here are some photos of the left control connector. There are six wires in the connector, they all match however there are two additional wires on the switch side: black and blue. Not sure what those are for. 

I know what your problem is, will get back to you tomorrow (it’s after midnight here in the UK

Wookie58 wrote:

I know what your problem is, will get back to you tomorrow (it’s after midnight here in the UK

🙏 THANK YOU!!! 🙏 you nailed it Wookie!! That was the solution. It’s working as expected now. 
while I have your expertise here, can you tell me where these two wires go? From the regulator and rectifier, I assume they are ground. Do I just bolt them to the frame? Is there a specific place?

danam wrote:

🙏 THANK YOU!!! 🙏 you nailed it Wookie!! That was the solution. It’s working as expected now. 
while I have your expertise here, can you tell me where these two wires go? From the regulator and rectifier, I assume they are ground. Do I just bolt them to the frame? Is there a specific place?

Yes they are grounds, in a perfect world I would attach them to the battery neg terminal but if they won't reach then a "chassis ground" would be "option B"