Passenger side running lights bright

Chris350

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Good evening everyone,
Before I dive deep into some electrical diagnostics, I’m hoping with all of your combined years experience with our trucks, some of you may have run across my problem before. So with no headlights on, everything works normal. Turn the headlights on and the passenger side lights are bright as if the turn signal is on but not flashing. With that said, when you do hit the right turn signal, nothing changes, they stay bright without flashing. I own a 1986 c10 5.0.
 

SirRobyn0

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Good evening everyone,
Before I dive deep into some electrical diagnostics, I’m hoping with all of your combined years experience with our trucks, some of you may have run across my problem before. So with no headlights on, everything works normal. Turn the headlights on and the passenger side lights are bright as if the turn signal is on but not flashing. With that said, when you do hit the right turn signal, nothing changes, they stay bright without flashing. I own a 1986 c10 5.0.
Look at your grounds first 99% of the time issues like this will be traced down to a ground. I suspect what is happening is you have a bad ground on the right side. This would most likely be at the right front light, possibly the tail light. If you have trailer wiring you could check back there too, but because the issue comes up when you turn the headlights on I think you'll find the issue at the RF. So find where the lights ground there at the RF and even if the ground connection looks ok take it apart. You want good clean contact, so use whatever you want to achieve that sandpaper or a wire wheel on drill set to slow speed works great. Once it's cleaned up apply dielectric grease to terminals and the body, to keep the ground from corroding or rusting. If you don't have dielectric grease you can get away with silicone grease like sil-glyde.
 

Grit dog

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^What he said. Tail lights have their own dedicated ground too. To the body right behind the light. And front turn/park lamps work as designed with rear ground/lights not connected.

And not contributory but anecdotal, apparently as evidenced by a previous owner of our 86, apparently filling the taillight bulb housings with axle grease does not affect their function!
When I removed the working tail lights from the truck, all the rear light sockets were packed with old crusty, been there so long it was cracked and caked on, what I’d call “tractor grease!”
 

SirRobyn0

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^What he said. Tail lights have their own dedicated ground too. To the body right behind the light. And front turn/park lamps work as designed with rear ground/lights not connected.

And not contributory but anecdotal, apparently as evidenced by a previous owner of our 86, apparently filling the taillight bulb housings with axle grease does not affect their function!
When I removed the working tail lights from the truck, all the rear light sockets were packed with old crusty, been there so long it was cracked and caked on, what I’d call “tractor grease!”
I've seen that on older rigs too, it's a pain to clean up, but at least the sockets won't be rusted and corroded! Replaced with dielectric grease. I can't say enough times how great dielectric grease is!
 

Turbo4whl

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Besides the ground already stated, the bulb could be installed 180 degrees backwards, or the wires on the socket could be reversed.

@Grit dog About that brown, look like axle grease, is bulb contact dielectric grease. Many manufacturers use it. Truck-Lite and others will even prepackage the replacement bulbs with the grease already applied.

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AuroraGirl

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@Grit dog About that brown, look like axle grease, is bulb contact dielectric grease. Many manufacturers use it. Truck-Lite and others will even prepackage the replacement bulbs with the grease already applied.
that?
 

Turbo4whl

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that?
Yes. Sure isn't pretty like the clear dielectric grease we all might be using on spark plug wires.
 

AuroraGirl

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Yes. Sure isn't pretty like the clear dielectric grease we all might be using on spark plug wires.
what did it start life as, dielectric grease can get opaque looking and kinda "crumby" esp if you use too much these days and esp on ignition circuit, but the stuff on our trucks also was used many years ago, so i assume maybe it looked nicer and wasnt always like indian shellac lol
 

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Yes. Sure isn't pretty like the clear dielectric grease we all might be using on spark plug wires.
I actually didn't know brown dielectric grease is or was a thing. When I've seen it, it's always been on older rigs, so was never sure if it was from age, or the wrong thing put in there (like WB grease). Regardless I'm a big believer in having a big tube of the clear stuff on hand and using it on literally every connection and socket that I take apart.

It's also great in outdoor lighting. On the farm we have a bunch on mercury vapor and a few sodium vapor lights that are up on poles. Since we started smearing just a small amount on the bulb threads and contacts we stopped having issues with frozen bulbs, and socket's needing to be replaced from corrosion. It's good stuff!
 

Turbo4whl

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@SirRobyn0

Truck-Lite must believe in it. They sure do sell lots of lights for commercial vehicles.

Price point, this is funny too:

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2 ounce tube from Zip's AW Direct towing supply, $16.99
Same from Drive train America $4.49

OR:

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8 ounce can from Amazon, $12.28 (free shipping)

Same from Find it Parts $9.31 + shipping

I could go on but I will stop. Pays you to shop around for everything you buy today. My question, how much is the tube of dielectric clear grease?

@AuroraGirl Taylor, the NYK 77 compound (grease) is brown to start with and it is waterproof.
 

Grit dog

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Besides the ground already stated, the bulb could be installed 180 degrees backwards, or the wires on the socket could be reversed.

@Grit dog About that brown, look like axle grease, is bulb contact dielectric grease. Many manufacturers use it. Truck-Lite and others will even prepackage the replacement bulbs with the grease already applied.

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Learn something new every day!
 

idahovette

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Dielectric grease also works well to slide boots on and off of spark plug wires.....if you need to
 

SirRobyn0

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@SirRobyn0

Truck-Lite must believe in it. They sure do sell lots of lights for commercial vehicles.

Price point, this is funny too:

You must be registered for see images attach


2 ounce tube from Zip's AW Direct towing supply, $16.99
Same from Drive train America $4.49

OR:

You must be registered for see images attach


8 ounce can from Amazon, $12.28 (free shipping)

Same from Find it Parts $9.31 + shipping

I could go on but I will stop. Pays you to shop around for everything you buy today. My question, how much is the tube of dielectric clear grease?

@AuroraGirl Taylor, the NYK 77 compound (grease) is brown to start with and it is waterproof.
Thanks for that. I had no idea a brown electrical grease existed.

So at the shop, and also in my tool box on the farm are the 3oz Permatex dielectric grease tubes.

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Orielly's Website shows them at $7.99 for 3oz. IDK what the shop actually paid probably something like $7.89 with the "deep" wholesale discount.

The .33oz, tube is $4.99, talk about interesting pricing. So that makes the 3oz tube, $2.69 and ounce, but the .33oz tube is $15.12 an ounce!!! That's the key right there, don't buy the little individual service packet or the tiny tube. Ask for the 3 ounce tube.

I'd consider ordering some of the NYK stuff just to try it, but I'm pretty sold on the Permatex dielectric grease at this point.
 

AuroraGirl

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I can attest that is good trick that makes it a whole lot easier.
its also helpful because it makes a dielectric interface when you put it on right. vehicles with very large gaps li9ke .060 you really get to appreciate keeping spark going to the electrode and not down the side of the insulator lol. and leaving a wire on for 100k.
 

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