Datsun Roadster Forum-311s.org

No power for the headlights passes through the dimmer switch for the headlights. The only power the dimmer switch gets is from the relay via the black/red wire that grounds the relay to trigger high/low.

So, there is no way that His problem is related to the headlight dimmer switch on column? Please advise. Pat

What if his column switch is not grounding correctly? Either way, you can't ignore the "director" of which headlights light up. Pat

If it doesn't ground to switch between high and low then one of them will be on.

Well, I had some time today and I had another idea I wanted to try something.

I figured that if something from the fusebox to the headlight relay was an issue, I could run a switch and the previously used 30amp inline wiring. So directly from the 12v to the switch to the headlight relay, replacing the red/yellow wiring and I had a switched headlight... not headlights! only the pass side was turning on. I couldnt remember if both were turning on when I directly wired the lights the prior attempt...

Still some progress though...

The next thing I wanted to try was to take the fusebox off and see if the rivet was loose, as Curtis previously mentioned to check out.

What I started staring at, just a reminder where I needed to put things back together.



Does the red wire look factory?'



After taking the fusebox off, I flipped it around and my thumb is on the rivet in question. Nothing seemed strange which was a bit disheartening, but also good that nothing looked bad.



A close up shot of other side of the rivet.



I looked to see if I had a another 30amp glass fuse and sadly I did not, but I used the test light to make sure the fuse was good and it was. Not really seeing anything out of the ordinary I put it all back together. Then I hooked up the red/ yellow wire back to the headlight relay and .... THEY WORK!

I have no idea how/ why / what/ who/ or anything but the lights were coming on with the switch.. well except the driverside light and turn signal. I was excited and also out of time, so I snapped some pics and called it a night.





Both rear lights on!



I have a brand new set of H4 lamps that I want to install, so hopefully thats a smooth process and I will have BOTH headlights and BOTH taillights functining to start, but Id like to improve the taillight situation to get all 4 as running lamps, but thats a project for another day.

The red wire may be stock but the black wires are not. You should have both headlights. I would check the headlight plug and the harness plug at the fender connection. And maybe the headlight too.

Simon,
To me the fusebox still appears to have a lot of corrosion . I think a Dremel with the tiny stainless brushes from Harbor Freight would clean it shiny in about 5 min.
https://www.harborfreight.com/5-piece-s ... 66129.html
Here are some pics and info on rivet repair too in case you have some loose ones:
viewtopic.php?f=2&t=29306
Linda

Well, you are making some headway. One light is better than none. (That was mostly a joke.) Tail lights work as well. Good work.

Will

FYI H-4 bulbs have a different wiring configuration than a sealed beam. You need to move some wires in the plug.

david premo wrote: ↑Tue Feb 18, 2020 10:53 am FYI H-4 bulbs have a different wiring configuration than a sealed beam. You need to move some wires in the plug.

Mine didn't. I think I used Wagner.

That will be the next thing, after I determine why the driverside headlight and running light arent working

Working on Linda's new harness this morning. Here's the stock wire on an original harness at the fuse box. As you can see no black wire, white and white/red stripe. You have been previous owner'ed.

Curtis wrote: ↑Tue Feb 18, 2020 12:09 pm ...You have been previous owner'ed...

(me to DAPO)


(Getting off topic a little)
Those two wires are related to the Alternator and ..?.. should I be worried?

Mine had some weird aftermarket alternator in it, that has been moved and converted to a modern "single-wire" Alternator

Can't say without seeing it in person. If the alternator works then probably not. They may have changed the wires because of a previous problem. The black is not original but as long as it is hooked up correctly then the color doesn't matter. Does your harness have signs of melting?

And this is why people want new wiring.

Yippee on my harness in the works!..
Going to try in the meantime the Deoxit spray, from www.caig.com, on all connectors since I read it is very good, even though everything working now. You can get a free sample from them...
You might try that Simon after a neg battery cable DC.
Sins of the PO, when electrical, can be problematic.
I would say , in my opinion, a new harness is a near requirement and ranks up there with the EI dizzy, and rebuilt carbs for the improvement on the reliabilty scale. New terminals, cleaning, connectors etc are great, but new and improved, in many ways, wiring is awesome.
Plug for Curtis, but there is also the Painless kit too for the DIY selfers.
Linda