Troubleshooting LED Trailer Lights Causing Error Code On 2021 GMC Sierra Denali 2500

Question:

I sold a 2021 Grand Design Solitude 5th wheel w/led lights to a couple that bought a 20GMC Denali 2500 Duramax to tow with. The trailer circut board in truck keeps burning out when plugged in. The turn signals flash, error code pop into the info screen of tow rig. Im needing help please.

asked by: Kelly L

Helpful Expert Reply:

To correct the issue the couple is having powering LED trailer lights with their 2020 GMC Sierra Denali 2500 I recommend going with the Trailer Connector Adapter w/ Lamp-Out Sensor Bypass # 20142 due to it being a simple plug and play adapter that installs in the vehicle's 7-way connector and you simply plug the trailer's 7-way connector into it. The built in system will prevent the issues you are having and will allow you to move the adapter to a different vehicle if needed.

The Optronics Load Resistor for LED Lights # ALEDRST1B you were looking at would require you to hardwire a resistor at every light to correct the lack of amps causing the error code when trying to use a trailer with LED lights.

It is not uncommon for newer vehicles to have an issue with powering LED trailer lights as the have so low of an amp draw compared to incandescent lights that the vehicle will think a light is burned out and throw an error code like you are seeing.

I included a video of the Trailer Connector Adapter # 20142 for you to take a look at.

expert reply by: Samuel C

Domenick C.

4/3/2024

2021 GMC Sierra. Trailer lights will sometimes work when first plugged in, then I can get all different signals on vehicle screen, “check connection”, “check turn signal” or “check brake lights”. It seems LED trailer lights aren’t drawing enough power, but incandescent will work. What can I do to make a trailer with LED lights work properly? Thank you, Domenick

Jon G.

5/7/2024

@DomenickC Thanks for reaching out! What you need is the 7-Way Vehicle Power Adapter # FR87PR. This essentially puts more of a draw on the truck 7-Way so the vehicle see the trailer as having incandescent lights which will solve all of the issues you're having.

Helpful Links

tv-demo-furrion-rv-camera-system-7-way-power-adapter-fr87pr.aspx