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1986.5 headlight electrical gremlin help..ghost lights!

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Old 07-24-2018, 10:40 PM
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Dundertaker
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Default 1986.5 headlight electrical gremlin help..ghost lights!

I installed a set of “VintageCarLeds.com” LED headlamps. I have 2 sets and they both work fine in my VW...so not a bulb issue.

First install and PRE-cleaning of the grounds and Panel I was getting 11.9v at the low beam pin. The HI beams go full bright because the controller assumes the low beams are out (safety mode in the controller per the manufacturer). So the seller advised I find my voltage issue. I replaced the light relay with a new one from Roger, pulled the panel and did the “cleaning” with DEOXIT and all the grounds were cleaned and checked. Fired it up and the same issue persists but the voltage did improve.

Lights on/key on: I get both beams in hi beam mode on low. Flipping the high beams makes them flicker and the blue bulb for HI lights up...fogs go off.
Pre cleaning: I got 11.9 volts at the LO pin at the light and 5.8v at HI pin
post cleaning: I get 12.1v at the low pin and 5.8v at the HI pin. Ground seems fine on my power probe...didn’t test the ground with it pre cleaning. And I get 12.2- 12.3 at the fuse on low.

I used a regular meter when I started and now pulled out my Power Probe 3 (PP)forgot I had it). Since the PP has a “tone and a light” I now noticed that at the pin the voltage made the PP “CHIRP” instead of a solid tone. At the fuse panel I get a solid tone (see video). So I don’t have a scope but assume the chirp means I’ve got a short or some other issue, but it only seems to be an issue with the key on. I tried switch8ng the HI and LO pins at the light and they worked as they should if I pu the stalk on HI the LO beams came on and HI worked on LO.....so the LO beam circuit has to be the issue and HI must be sending clean voltage.

light switch on, lo beam, key on:


New issue: since I installed the fresh relay, the lights now sometimes stay on and work normally (lo and hi beams) with the switch off....key off...and wiggling the relay will turn it off, then sometimes they will flicker and turn on by themselves. So I played with it and shot a video showing the issue.

Light switch off, key off (ghost lights working normally:


Any help would be greatly appreciated.
Dan
Old 07-26-2018, 02:18 PM
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davek9
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Have you replaced the FOG light relay with a standard type53 ?

Also the Head light should not work with the Key in the off position, but the parking light will.
If the Headlight are working with the Key in the off position, I'd look at the Ignition switch it's at the back of the Ignition Key mechanism, sometimes it also affects the windows, and other things.

Dave K
Old 07-26-2018, 02:22 PM
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Dundertaker
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I have not, I have some extra 53's and will try. Could you please explain what that would do. (Thanks for the reply)

DG
Old 07-26-2018, 02:28 PM
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davek9
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There are in depth explanations in other threads, you can search them out, in short it has to do w/ the using an electrical path through the headlight "Bulbs" to cancel out the FOGs from working w/ the Headlights in Hi beam mode.
Old 07-26-2018, 03:05 PM
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Dundertaker
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Originally Posted by davek9
There are in depth explanations in other threads, you can search them out, in short it has to do w/ the using an electrical path through the headlight "Bulbs" to cancel out the FOGs from working w/ the Headlights in Hi beam mode.

Will do....if you solved this for me I’m adding you to my Will....It’s driving me nuts!

Thanks.

DG
Old 07-26-2018, 03:29 PM
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Originally Posted by davek9
There are in depth explanations in other threads, you can search them out, in short it has to do w/ the using an electrical path through the headlight "Bulbs" to cancel out the FOGs from working w/ the Headlights in Hi beam mode.
Thanks Davk9.....I vow to search harder next time. This solved one problem. https://rennlist.com/forums/928-foru...led-bulbs.html

Last issue is lights staying on with power off........and wiggling the relay to shut them off. I've cleaned the panel, etc....as noted. I'm going to do more research, but if anyone has a quick recommendation on trouble shooting this I'd appreciate the help.

DaveK9 I will leave you all my lubricants and magic cleaning supplies upon my death. Thank you!

DG



Old 07-26-2018, 04:24 PM
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LOL
Your most welcome !
Old 07-27-2018, 12:46 PM
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dr bob
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Confirm that the grounds for the bulbs are clean and intact. LEDs are funny in that they are polarity sensitive but can leak if the grounds aren't perfect.
Old 07-31-2018, 01:07 PM
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Originally Posted by dr bob
Confirm that the grounds for the bulbs are clean and intact. LEDs are funny in that they are polarity sensitive but can leak if the grounds aren't perfect.
Was gone all weekend.....I will double check the grounds and clean the connections at the headlights with "Deoxit" (Just realized I had cleaned everything BUT those.)

Currently I'm leaving the headlight switch in the ON position and the FOGS on and just using the KEY to ON/OFF lights.......because I didn't have the Headlight covers on the back of the lights. thought about that over the weekend and wondered if that may be part of the issue? I'm going to button everything up and make sure it's not a "bleed" from any of those ON position switches, etc...and see where we are at. Thanks for the advice all.

DG



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