68 2000 light problem

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2mAn
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Re: 68 2000 light problem

Post by 2mAn »

well, finally getting back to this...

I was determined to see the lights turn on, and have been suspicious about the fusebox because that seems to be the most common issue on the 68. I decided I would give it a shot at bypassing the fusebox. Wiring diagram in hand, some spare wiring bits and I decided this would be an easy tell if the fusebox was no good.

Image

This didnt do anything, so I put it back together and stared at the relay...

**I know this isnt the smartest move. Desperate times call for desperate measures lol **

I had my wiring diagram in hand and ran power directly from the battery to both the red/white wire, and then the red/black wire and both headlights turned on both times. Ok, so that means the lights work and arent getting power... whats next.

From there, I was looking at the relay. I pulled it apart and everything looked good, but then when I went to reinstall it I noticed that mine isnt labelled D -S-M-B (not sure if thats the order, just rattling off the letters off the top of my head). Mine is labelled 1-2-3-4.

Image

Whats up with this?...

I had a Bosch relay laying around and the wiki showed where the wires should go, hooked them up and tried again... still nothing...

Next thing I wanted to do was to see if theres power getting from the fusebox to the red/yellow wire at all. Test light hooked up and nothing.

At this point I wondered if the power is even at the fusebox, but test light showed that every connection at the fusebox was lighting it up, except the headlight connection, after the fuse. This confused me because shouldnt have bypassing it worked then?...

Any thoughts or direction is appreciated

Thanks
Simon
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-1999 Porsche 911 4/98-build, 3.8L M96
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2mAn
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Re: 68 2000 light problem

Post by 2mAn »

(From a helpful person)
(Pasted here for future reference when I can actually attempt this)

Ohm it out. Set the multi meter to ohms, one side on the top, the other side on the bottom of the fuse contacts and see what it reads. Check the one next to it and see if its any different.

If there is no power on the out side of the fuse, but there is on the in, that means there is an issue with the fuse contacts. If there is power in and out of the fuse block, the issue lies between the fuse box and the turn signal/high/low beam switch on the column. If you have power coming out of there, then the issue likely lies between there and the relay. (a chewed wire.)
Simon
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Curtis
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Re: 68 2000 light problem

Post by Curtis »

Two things can wrong at the fuse box. The clip and rivet connections can be loose or corroded. The glass fuse can be bad and you can't tell. Sometimes they break on the inside at the ends where you can't see it. Replace it.

Try these.

http://www.kendo-usa.org/datsun/66_68_h ... rewire.pdf
http://www.kendo-usa.org/datsun/datsun_ ... out_68.pdf
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2mAn
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Re: 68 2000 light problem

Post by 2mAn »

Curtis wrote: Thu Feb 13, 2020 11:32 am Two things can wrong at the fuse box. The clip and rivet connections can be loose or corroded. The glass fuse can be bad and you can't tell. Sometimes they break on the inside at the ends where you can't see it. Replace it.

Try these.

http://www.kendo-usa.org/datsun/66_68_h ... rewire.pdf
http://www.kendo-usa.org/datsun/datsun_ ... out_68.pdf
Thanks Curtis, I printed those out to use later. I already had a few other PDF printouts of yours and they are extremely helpful.

The glass fuse looked good and has been replaced recently, but I can certainly replace it easily. The Test light lit up on both sides of the fuse mount, not sure if that means anything, but I will check out the clip and rivet connections next. However, that said, when I bypassed the fusebox, I used that inline fuse and connected the two sides to it and still wasnt getting anything. I believe the fusebox is one of possibly 2 issues.
Simon
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-1999 Porsche 911 4/98-build, 3.8L M96
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Re: 68 2000 light problem

Post by Linda »

Some of the relays are labeled 1234 so you just have to be sure wires aren’t switched. Info in past threads. Also clean tabs and the mounting point on the car well.
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Re: 68 2000 light problem

Post by Curtis »

If the tail light, park or fog lights work then I would suspect the light switch or wiring from the switch to relay.
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Re: 68 2000 light problem

Post by 2mAn »

Curtis wrote: Thu Feb 13, 2020 12:26 pm If the tail light, park or fog lights work then I would suspect the light switch or wiring from the switch to relay.
I have one single brake light that works! haha also the right side turn signal also, nothing else does
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Re: 68 2000 light problem

Post by Curtis »

Brake and turn unrelated to headlights.
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Re: 68 2000 light problem

Post by 2mAn »

Curtis wrote: Thu Feb 13, 2020 1:58 pm Brake and turn unrelated to headlights.
Perfect, so first thing I want to confirm is that the clip and rivet are in good condition, or at least fix them.

Can you direct me to what would make it obvious that its messed up? The previous page has the pics from when I pulled the fusebox and soaked it in vinegar.
Simon
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Re: 68 2000 light problem

Post by Curtis »

2mAn wrote: Thu Feb 13, 2020 3:10 pm
Curtis wrote: Thu Feb 13, 2020 1:58 pm Brake and turn unrelated to headlights.
Perfect, so first thing I want to confirm is that the clip and rivet are in good condition, or at least fix them.

Can you direct me to what would make it obvious that its messed up? The previous page has the pics from when I pulled the fusebox and soaked it in vinegar.
You have wiggle each one of them I think. See if anything will kind of spin. I've never had to do it and I just have one on hand for my harness building.
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Re: 68 2000 light problem

Post by unklpat »

When I bought my car last year, The horn would only work at certain clock positions, no headlights except every now and then. I was stranded one night and slammed the hood in frustration, and lights came on. Car came with new used turn signal lever assembly (floppy old one) that I installed, and Lights work every time. I think the dimmer switch is before the relays. Added led bulbs in hella housings, and WOW! I guess dimmer switch is your problem. Let us know. Pat
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Re: 68 2000 light problem

Post by Curtis »

The dimmer power comes off of the parking light circuit and would have nothing to do directly with headlights.
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Re: 68 2000 light problem

Post by unklpat »

My headlights would not work, until I swapped out the dimmer/turn signal assembly. I believe the headlight switch routes power thru the dimmer assembly, then to either high/low beam at relay. Please advise, if I am wrong. Pat
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Re: 68 2000 light problem

Post by Curtis »

unklpat wrote: Fri Feb 14, 2020 11:35 pm My headlights would not work, until I swapped out the dimmer/turn signal assembly. I believe the headlight switch routes power thru the dimmer assembly, then to either high/low beam at relay. Please advise, if I am wrong. Pat
No, it doesn't.

http://www.kendo-usa.org/datsun/datsun_ ... out_68.pdf
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Re: 68 2000 light problem

Post by unklpat »

I am trying to say headlight dimmer, or high/low switch, and yes I believe it does go from headlight switch thru headlight dimmer on column, to relays. Pat
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