Trailer lights

[Larry Connally]

I have a trailer that I have towed for over 7 years with my 2006 duramax. I hooked new 2019  duramax to it and the only lights that work are hazards and park lights. Brakes don’t work hooked up to the 2019 either.  Power at plug. Hooked back up to the 2006 and everything works. Hooked up to my buddies 2012 Ram and everything worked.

Any ideas?

thanks

[In2racn]

This trailer light flicker issue concerns me... if I leave my trailer connected for a week, I risk killing the battery. Hard to believe this is "normal". 

 

 

Video of trailer lights flickering... don't mind the mutt.

[Major Tom]

On 11/10/2019 at 11:23 PM, In2racn said:

This trailer light flicker issue concerns me... if I leave my trailer connected for a week, I risk killing the battery. Hard to believe this is "normal". 

 

 

Video of trailer lights flickering... don't mind the mutt.

Not an expert, but this might be the truck's security system just checking to make sure the trailer is still connecter to your truck.  The current flashed to the trailer wiring harness may be enough to get the LED trailer lights to flash, but not enough to light up older incandescent bulbs.  Just my guess.

[powerhaulic]

13 hours ago, Major Tom said:

Not an expert, but this might be the truck's security system just checking to make sure the trailer is still connecter to your truck.  The current flashed to the trailer wiring harness may be enough to get the LED trailer lights to flash, but not enough to light up older incandescent bulbs.  Just my guess.

That is correct

Edited November 17, 2019 by powerhaulic

[AT4 HD Ron]

I turned off the trailer theft feature yet the trailer lights still flash the same. 

[JOSE E ALFARO]

I have a 2020 Denali Duramax, I'm having issue,  when truck is off, the trailer lights stay on, first time I connected the trailer it drained my battery, then i noticed I get a pulsation on the trailer break lights.  does anyone know if this is a know issue?  Or do I have to disconnect the trailer ever time I turn off the truck?

[Garett Dixon]

I am having the same issue with my 2020 GMC AT4. I have LED lights on my boat trailer and they are not working correctly. I had no issues with my ram 3500. Did the dealership find a way to make yours work?

[Jordan94]

1 hour ago, Garett Dixon said:

I am having the same issue with my 2020 GMC AT4. I have LED lights on my boat trailer and they are not working correctly. I had no issues with my ram 3500. Did the dealership find a way to make yours work?

So I got it into the dealership a while back and they replaced the trailer light control module and it still didn’t fix anything. After that they were able to steal a receptacle off of another truck and swap it onto mine and establish that it was just a faulty receptacle. It’s worked perfectly since they replaced that. 

[Chad20highcountry]

I have a 20 high country was having the same trouble no power to the plug .was trying to hook up a led backup lamp. Found a set of towing lights plugged in inside the box and it was enough to send power to the bumper plug .works good so far

[Shredz]

2020 denali hd is experiencing light issues.  Doesn't like my new marlon 2020 sled deck. Running lights will work until I hit brakes or directional. This is just the beginning of my issues as now I want to hook sled trailer to the as well. Anyone figure this out yet?

 

[Christopher Murphy]

On 12/21/2019 at 5:55 AM, Shredz said:

2020 denali hd is experiencing light issues.  Doesn't like my new marlon 2020 sled deck. Running lights will work until I hit brakes or directional. This is just the beginning of my issues as now I want to hook sled trailer to the as well. Anyone figure this out yet?

 

Best advice I can give you is to thoroughly read this TN https://gm-techlink.com/?p=11176

It's very important to confirm you are below the total 30amp overall load. These trucks have a very finite allowance. Typically having all LED lights proves to be the best. Since you are experiencing issues only when turn signal is on or brake applied I am thinking you are over when adding the additional amperage when braking or signaling. 

[Ryan Evans]

I got the adapter buddy was talking about earlier in this thread. It works flawlessly. Problem solved.

[Chuyito]

What adapter?  My truck is doing the same thing, left blinker and left stop light otherwise everything else works, same trailer on my 2006 dually works just fine.

[SkidooSteve12]

On 12/28/2019 at 2:14 AM, Chuyito said:

What adapter?  My truck is doing the same thing, left blinker and left stop light otherwise everything else works, same trailer on my 2006 dually works just fine.

 

This is the 7-way plug adapter that was recommended. Sounds like it has been a hit or miss issue with some trucks and LED trailer lights. My trailer with LED lights and brakes works fine with my new 2020 HD.

 

https://www.curtmfg.com/part/57003

 

[M3rlin]

I have a brand new 2020 Chevy 3500. Bed plug works fine on my 2006 Platinum LQ trailer with EOH brakes.

 

Tried to use my 2014 Sundowner bumper pull and the Park Lamps (running lights) and Trailer Brakes won’t work. The rest of the lights and signals work fine. At times the truck will not even recognize the that the trailer is connected. 
 

All fuses in truck are fine, replaced trailer plug and same thing. Hook trailer to my 2017 F-350 and everything is fine.