Trailer Running Lights

[timswi]

Op here

Turns out the fuse blew in the truck. Fixed that, plugged it back in and started shaking lights/wires etc..Had it running for 1/2 hour and didn't blow the fuse again. Inside the truck 7 pin and the trailer plug both look like new--I dialectric greased them a while ago...I did lift the pins on the trailer plug a bit for a better connection. Still doesn't make sense..Gotta be a bare wire somewhere or the 1 in a million weak fuse. Guess I gotta crawl around under it and get a better look.

 

[CobyRupert]

Op here

Turns out the fuse blew in the truck. Fixed that, plugged it back in and started shaking lights/wires etc..Had it running for 1/2 hour and didn't blow the fuse again. Inside the truck 7 pin and the trailer plug both look like new--I dialectric greased them a while ago...I did lift the pins on the trailer plug a bit for a better connection. Still doesn't make sense..Gotta be a bare wire somewhere or the 1 in a million weak fuse. Guess I gotta crawl around under it and get a better look.

What do you mean you dielectric greased the pins and plug?
Dielectric Grease

"Dielectric grease is non-conductive so if the user does not properly clean the conductor’s contact points after applying dielectric grease, current will not pass through them. "

Maybe somebody can correct me if I'm wrong, but my understanding is the pin and receptacle should have good metal on metal contact (like a battery post and cable clamp). The dielectric grease would be to coat the metal that is in contact with air (not conducting surfaces) and block it from air, moisture, dirt etc.. so exposed metal doesn't corrode.
That is, you shouldn't have dielectric grease on the metal conductor part (pins, receptacles) that contact each other.

 

[Ford850]

^^ Dielectric grease prevents oxidation and provides some lube for easier connecting. When plugging in, the pins scrape through and make a good clean contact. Many plug kits come with the grease too.

 

[Diggin It]

Dielctric grease is commonly used in connectors to keep water and corrosion out. It does not interfere with conductivity as long as the connectors are seated fully and in good condition.



OP, consider load. How many marker lamps and running lights, what wattage, incandescent or LED, etc. If you have too many lamps drawing too much current, they may simply overload the fuse.

 

[countrybumpkin]

Yes that is true, if applied incorrectly. As with anything it has its pros and cons depending on the use. On my plugs I just keep them clean and dry, with no issues.

 

[Ford850]

Op here

Turns out the fuse blew in the truck. Fixed that, plugged it back in and started shaking lights/wires etc..Had it running for 1/2 hour and didn't blow the fuse again. Inside the truck 7 pin and the trailer plug both look like new--I dialectric greased them a while ago...I did lift the pins on the trailer plug a bit for a better connection. Still doesn't make sense..Gotta be a bare wire somewhere or the 1 in a million weak fuse. Guess I gotta crawl around under it and get a better look.

I had the same thing happen on an older trailer, affecting the running lights. I finally found the worn bare wire that occasionally shifted and caused the short, blowing the truck fuse.

 

[pmsmechanic]

I have several trailers. The trailers that never have lights issues are the trailers that I have redone the wiring on and ran a separate ground to every light. It's money and time well spent. I'm also a solder and heat shrink type of guy. Do it once and basically never have issues with that wiring connection again.

 

[CobyRupert]

It does not interfere with conductivity as long as the connectors are seated fully and in good condition.

If OP coats conductors (pins and sockets) with a non-conductive grease, essentially insulating them, how can this not interfere with their conductivity?

Relying on the plug and receptacle to wipe themselves off when you push one into the other and make good conductive contact might not be fool-proof. :2cents:

 

[ruffdog]

If OP coats conductors (pins and sockets) with a non-conductive grease, essentially insulating them, how can this not interfere with their conductivity?

Relying on the plug and receptacle to wipe themselves off when you push one into the other and make good conductive contact might not be fool-proof. :2cents:

They use dielectric grease in components like ignition switches too. Could you imagine if they used a conductive grease like a copper grease? You would have cross terminal arcing...NOT GOOD!

 

[grsthegreat]

Ive seen dielectric grease used I’m many..many electrical situations over the years. Never caused any issues. Even says to use them in spark plug boots for my jet ski in the manual.