My first electrical problem

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thesameguy
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My first electrical problem

Post by thesameguy »

Took over 15 years for me to have my first actual electrical problem with the XR. After spending an hour going through wiring diagrams and checking the multimeter the problem appeared to be a bad ground on the right rear tail light. My quick fix:

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I tied these back to the main G101 ground near the license plate lights, and most of the problem was solved.

Turns out I have a second, unrelated problem... which is the right front turn signal doesn't work. The ground is solid but for some reason there's only 3v on the positive side. Wiring diagram shows all four corners tie back to one splice, so I guess I got some digging to do. I've got brake lights and tail lights again - FR turn signal is a low priority. :D
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andyofcolumbusmerkur
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Re: My first electrical problem

Post by andyofcolumbusmerkur »

I did that when I first got the Merkur, and it helped. But every year I have to pull that stuff apart and clean everything to make them work correctly. No big deal really. Never needed to do this with any other cars however. May try some ultra high tech products I have read about on this forum instead of just the little packet of bulb grease. It seems like climate has a lot to do with it as yours look pretty clean.
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zxr250cc
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Re: My first electrical problem

Post by zxr250cc »

Hi all,

I note the mention of bulb grease and I wonder if you mean dielectric grease? That is meant to help with water proofing and is not meant to be a conducter. I use it to keep boots sticking on spark plugs. If you use it on battery terminals that should be applied on the outside after the clean terminals are tightened up, not on the post inside the clamp.

There are chemicals available from CRC and others that are designed to improve conductivity and reduce corrosion. I would suggest they are better than bulb grease for this.

YMMV

Cheers
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thesameguy
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Re: My first electrical problem

Post by thesameguy »

The connectivity issue doesn't appear to be at the bulb... at the taillights it was clearly the main connector just being an '80s design. I've run into the exact same thing on numerous '80s euro cars.

The front turn signal issue is weird. I think it's splice S145 where all the turn signals come together, but I don't know where that is and didn't immediately see it in the EVTM. But, also, I was thinking about this last night and I may have misread the diagram. I may misunderstand how the turn signals & hazards work... neither of them illuminate the RF bulb.
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andyofcolumbusmerkur
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Re: My first electrical problem

Post by andyofcolumbusmerkur »

zxr250cc wrote: Mon Oct 04, 2021 9:05 am Hi all,

I note the mention of bulb grease and I wonder if you mean dielectric grease? That is meant to help with water proofing and is not meant to be a conducter. I use it to keep boots sticking on spark plugs. If you use it on battery terminals that should be applied on the outside after the clean terminals are tightened up, not on the post inside the clamp.

There are chemicals available from CRC and others that are designed to improve conductivity and reduce corrosion. I would suggest they are better than bulb grease for this.

YMMV

Cheers
Ya I only learned a couple years ago about dielectric grease not actually improving conductivity. In the past I put it all over, and everything still worked fine afterwards. Spark plugs light bulbs etc. Nothing corroded inside and performance stayed consistent. I think that when the items are tight together it pretty much pushes out the grease, and leaves more grease in the small spaces. I still put it over the spark plug or bulb or battery terminal, but now wipe off some with a small cloth. I just don't like the idea of that corrosion bloom pushing metal contacts further and further apart. I usually buy the crc carb spray for outdoor power equipment, and their electrical contact cleaner spray can as well. I never use that red spray stuff I see people use on the outside of battery terminals.
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Ed Lijewski
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Re: My first electrical problem

Post by Ed Lijewski »

Tail light issues are mostly due to poor contacts in the harness connection and bulb contacts points.

Adding the separate ground wire didn't work in my issue.

The female spring connectors in the harness connection can be removed, then bending them to get better purchase on the prongs which are often oxidized.

In the bulb modules, the inner spring contacts can be bent upwards a bit to make better contact with the bulbs.
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YMMV
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andyofcolumbusmerkur
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Re: My first electrical problem

Post by andyofcolumbusmerkur »

My bulb holders (modules) were really crusty (oxidized) so I got some nicer ones from Merkur Depot. It seems like the design is a little different on the newer cars verses the older cars. Not sure if they are any better. I still added the extra ground wire. He told me to pull it all apart, spray it with WD40 and brush it with the small brass brush you buy in the 3 pack at the autoparts store. Then I put bulb grease on the bulbs just like it shows on the packet. The packet has an arrow pointing to the metal part so users know not to put it all over the glass part. After all that it only works correct for a year. In the spring I always have to redo this process. So I think I am going to try something like stabilant 22 after getting it really clean with CRC electrical contact cleaner.
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Ed Lijewski
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Re: My first electrical problem

Post by Ed Lijewski »

Using a piece if small wire push the retainer clip to release the female connector. Then clean and tighten the spring connectors.
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Given its cost (was ~ $50 when I bought a vial 15+ years or more ago...) Stabilant 22 is best saved for EEC connections, and the copper infused product recommended by brokencase for other electrical contacts.

YMMV
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andyofcolumbusmerkur
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Re: My first electrical problem

Post by andyofcolumbusmerkur »

Ya I was thinking about trying that Kopr Shield stuff after reading about it here. Sounds like good stuff. I switched out all the old bulbs with brass bases for new shiny Sylvania ones with shiny silver bases this spring. Thanks person(s) that left them in vehicle that was then sold to pull a part! :D
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