No Trailer Connected Issue

[Leon Baehre]

running a 2020 2500 Duramax LTZ dbl cab pulling a 20foot travel trailer.  Dealer setup TPM with no issues. We are on our first road trip, going to be out for 7 weeks and about 4000 miles.  Truck has 1700 miles and is a dream to travel with. Tried to check the TPM and am getting the message that there is no Trailer Connected. The trailer is connected, trailer lights are working, trailer brakes working. How to resolve?

[MTU Alum]

Did you happen to hook the trailer up and plug in your 7 way connector when the truck was running?  The best way I have found is to shut off your vehicle when you are hooking up.  Hook up the trailer and chains before plugging in the seven way.  Ideally, plug the seven way in after the truck goes asleep.  Easiest way to tell the truck is asleep is if the light by the onstar symbol is out.  

 

I have also seen after you start the vehicle it may not recognize a trailer is attached until you depress the brake pedal.  

 

Hope one of these help you out.

 

#iworkforGM 

[Leon Baehre]

Hope you have the solution.  I did have the truck running when I hooked it up.  I just went out and unhooked the trailer wiring.  I will rehook in the morning before I start the truck.  I will follow-up tomorrow with the result.  Thank You very much for the quick response. Cheers

[hotairgypsy]

i have several trailers i hook/unhook too and i run into it saying i have no trailer hooked up right after i just hooked up the trailer...i just go to the trailer profiles and select my trailer and all my info is there

[Mi99z71]

Does the trailer have LED lights? I read in another topic that sometimes there isn't enough load on the lights to sense the trailer. There is an adapter that one can purchase on Amazon. It plugs into the 7 way plus and then you plug your 7 way trailer into it. Puts electrical load on truck to see it there.

https://www.amazon.com/gp/aw/d/B00C4AYR3U?psc=1&ref=ppx_pop_mob_b_asin_title

 

On the plus side, you can run just the adapter without a trailer and when you turn on signals, if you have the 360 cameras- the truck will switch and display that side of truck's blind spot in the radio.

 

[Leon Baehre]

Just returned from a 4 week trip to Texas with the travel trailer and had numerous problems with "no trailer connected" issues.  Truck always recognized trailer connection, lights work, gain and tow mode restored, but often the "no trailer connected" when I check trailer for TPM. Doesn't matter if truck is off when plugging in the trailer. If I stop for fuel and unplug and replug, it might start working.  We do not have LEDs on the exterior trailer lights.  I will take the truck in for its first service once the pandemic passes and hopefully they can figure it out. Of course that will require dragging the trailer along and surely, it will work then. PIA. Also get numerous warnings about a failed blinker which if false of course.

[Thomas Karr]

When I plug my 2019 GMC 1500 Sierra into my travel trailer it shows no signal to my rear facing furion camera on the trailer. I can put a jumper in my seven way plug on the trailer and make the camera show on my plug in monitor. As soon as I plug it into my truck with the lights on and truck running it shows no signal to my camera. My RV supplier told me mine was the third GMC/Chevy 2019/2020 trucks in the last two weeks with this problem. Glich is in the vehicles. What’s the problem. My trailer is presided for the furion camera.

[Leon Baehre]

 The No Trailer Connected issue has gotten more complicated.  I have a car trailer with LED lights and have the same issue. The dealer has been really good about trying to resolve the issue.  They replaced the ECM under the spare tire and the 7 pin connector.  We have the same issue even with the new components. Plus it is now worse, the system loses its memory of the pairing to the TPMS. We just returned from a 8 day trip from Michigan and had multiple issues, had to stop by a Chevrolet dealer midpoint in the trip to relearn the TPMS which they did very promptly.  Local Dealer is working with Chevrolet to come up with a solution. 

 

[shadow gray 2020 hd]

Having an issue with mine lately.  Trailer will be fine, then driving along will pop up no trailer detected.  Just this morning, my lights were on and brakes were working, then halfway to where I was going everything quit working and message popped up no trailer detected.  I pulled over and unplugged the 7 way plug and plugged it back in, still would not work.  Luckily, was just a short trip with my 22 ft equipment trailer and some oak logs.  

 

My electronics seem to be having some gremlins, having other non trailer related screwy issues as well.  Another complaint for the dealer.  

[Fast325it]

Has anyone found a fix for these gremlins? I’ve got 27,000 miles on my 2019 Silverado and the “no trailer connected” issue just started with a snowmobile trailer I’ve towed many thousands of miles and had no problem. It has LED lights and everything functions normally when connected to other vehicles. I have other trailers with both incandescent and LED lights and those trailers all work fine. 

Edited August 8, 2022 by Fast325it

[GMCustomerService]

On 8/8/2022 at 10:34 AM, Fast325it said:

Has anyone found a fix for these gremlins? I’ve got 27,000 miles on my 2019 Silverado and the “no trailer connected” issue just started with a snowmobile trailer I’ve towed many thousands of miles and had no problem. It has LED lights and everything functions normally when connected to other vehicles. I have other trailers with both incandescent and LED lights and those trailers all work fine. 

This is certainly not what we like to hear, Fast325it.  Please know, customer satisfaction is extremely important to us. Our team would be more than happy to take a closer look into the concerns with your 2019 Silverado. To do so, please send an email to [email protected] with ATTN: Fast325it/GM Trucks in the subject line.

Please include your contact information, VIN, a brief description of your concern, and the name of your preferred dealership. We look forward to hearing from you. To learn more about GM’s privacy policy, please visit https://www.gm.com/privacy-statement.html.
 
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[JakeJ]

2020 Sierra AT4, throwing no trailer detected, randomly. Lights not responding, no trailer brakes luckily it’s only a single axle, I have ruled out the wiring on the trailer. What can I do seems the truck has issues somewhere? 

[GMCustomerService]

On 12/29/2022 at 6:07 PM, JakeJ said:

2020 Sierra AT4, throwing no trailer detected, randomly. Lights not responding, no trailer brakes luckily it’s only a single axle, I have ruled out the wiring on the trailer. What can I do seems the truck has issues somewhere? 

This is certainly not what we like to hear, JakeJ.  Please know, customer satisfaction is extremely important to us. Our team would be more than happy to take a closer look into the concerns with your 2020 GMC Sierra AT4. To do so, please send an email to [email protected] with ATTN: JakeJ/GM Trucks in the subject line.

Please include your contact information, VIN, a brief description of your concern, and the name of your preferred dealership. We look forward to hearing from you. To learn more about GM’s Privacy Policy, please visit https://www.gm.com/privacy-statement.html. The information you provide may be monitored and recorded and is subject to the GM Privacy Statement.
 
Privacy Statement | General Motors
Your privacy is important to General Motors. This Privacy Statement addresses the personal information GM collects and how GM handles that personal information.
www.gm.com
 

[airbusdriver]

Just ran into same thing with trailer lights. 2013 suburban trailer lights work on 4 place snowmobile trailer. When I try it with my 2020 GMC 2500HD AT4 I get no trailer connected. Brake controller works but no trailer lights on trailer work. This is the first trailer I have had an issue with on the GMC. I purchased truck used in May 2021 and it just turned over 30,000 miles, 36 month warranty just ended in Sept. The dealer is going to try a new light module except it will take a week and I wanted to pull the snowmobile trailer this weekend. No quick fix. Going to try either putting in LED lights and or unplugging some of the marker lights to get trailer draw down to work some of the lights. 

[airbusdriver]

Just ran into same thing with trailer lights. 2013 suburban trailer lights work on 4 place snowmobile trailer. When I try it with my 2020 GMC 2500HD AT4 I get no trailer connected. Brake controller works but no trailer lights on trailer work. This is the first trailer I have had an issue with on the GMC. I purchased truck used in May 2021 and it just turned over 30,000 miles, 36 month warranty just ended in Sept. The dealer is going to try a new light module except it will take a week and I wanted to pull the snowmobile trailer this weekend. No quick fix. Going to try either putting in LED lights and or unplugging some of the marker lights to get trailer draw down to work some of the lights.