[locomotiveengineer]

I am having problems with my trailer tail lights. The turn signals and brake lights work, but the tail lights do not. I want to disconnect the pig tail plug to put in a jumper from the actual right tail light. Cant't seem to get it disconnected from the back of the trailer plug in. Any Ideas?

 

[blueiceRAM]

Do you have a 4 pin or 7 pin? I pull trailers all the time and every once in a while when things like that happen (I have 7 pin), I spray a little wd40 inside the plug on the truck. It seems to help all pins make better contact. If that don't work then probably a bad ground

 

[locomotiveengineer]

Thanks for your reply. I also have the 7 pin as well as the 4 pin plug above 7 pin. I will try the WD 40 inside the plug, and then look for a bad ground. Thanks again.

 

[blueiceRAM]

Our northern climate is brutal on trailers and electrical components. Those are just a few things that are typically most common issues. Hope it works out for you

 

[Turbovsix]

I have good luck with that CRC electrical connector spray - it cleans, but also lubricates, and is safe on the plastic housings as well. I had an issue with a new boat/trailer this past year that was very similar to yours. On my trailer, there are two ground wires that exit out of the tail lights on the trailer and they are grounded to the trailer. I removed them, scraped down to the paint on the trailer under the washer and that fixed my issue. It was like an intermittent problem.

But yeah, use that CRC stuff from time to time and it seems to keep everything in good working order.

I also bought this gizmo that I carry on my boat keychain and it plugs into the trailer light receptacle on my truck (the 4 pin) and it lights up to tell me if any of those pins are bad (easier than carrying a test light around). This way, at least I can quickly eliminate the truck as the issue.

Not long ago, I also discovered a broken ground strap on my truck down by the firewall. Dealer replaced it. Prior to that, I seemed to go through a lot of bulbs on the truck - that seems to have fixed the issue. So yeah, a bad ground can manifest itself in a lot of strange ways. Trailer lighting issues are a pain.

 

[MisterGDRam]

Thanks for your reply. I also have the 7 pin as well as the 4 pin plug above 7 pin. I will try the WD 40 inside the plug, and then look for a bad ground. Thanks again.

If you have bad ground you wont have even turn signals or stop lights.
Most likely the problem is at the trailer wiring.

 

[docboblv]

Hello everyone,I ve got a 2011 3500 and having issues with my KZ ESCALADE trailering lights..NOTHING,no brakes,no tail ,turn or clearance....I RAN A WIRE SUSPECTING A GROUND ,nothing,,,,,I have NOT tried the WD or the contact stuff but will in the morning ...I tested the truck and it shows working according to the tube tester....frustrating.