2021 Yukon Denali Trailer Brake Control Disconnect

[Meyersrl]

I have a 2021 Yukon Denali wit the max trailering package including the integrated brake controller. Unfortunately Im running into an issue with my electric over hydraulic brakes on my boat trailer. I can't drive the car more than about 100ft before it says check wiring then trailer brakes disconnected. Boat trailer is a brand new triple axle and I have had the dealer check the ground, trailer control module etc. I have sat in two of their trucks to test towing the trailer and no issues, however their trucks were a 2014 and 2015 silverado with integrated brake control. I have taken my yukon to my local GMC dealer and they say the cars controller is working fine but they see a C1114 error code. I have talked to another dealer who is closer to where people boat and the first thing they asked is if the trailer had all LED lighting. It does have all LED lighting and he immediately said they are seeing issues for 2021s where there isn't enough current due to the low voltage LED lighting on the trailer and the car then assumes the trailer is disconnected and shuts of the trailer brake control. He also mentioned that GM does not have a fix for this and to speak with a trailer company about possible solutions.

Has anyone else heard of this being an issue on the newer 2021s? I am aware of the potential need to add resistors when using LED on the trailer for this but Im trying to confirm if this is a possible cause of my issue. I might be wrong but based on some searching it seems the car wants a minimum of 55 miliamps current to detect the trailer?

Any info would helpful as Im getting stuck since GMC is saying the car checks out.

 

[Northern Mi Rich]

I’ve got the SLT with the trailer package. I’ll be picking up my travel trailer in a couple of weeks - if I have this issue I’ll post it.

 

[Geotrash]

I have a 2021 Yukon Denali wit the max trailering package including the integrated brake controller. Unfortunately Im running into an issue with my electric over hydraulic brakes on my boat trailer. I can't drive the car more than about 100ft before it says check wiring then trailer brakes disconnected. Boat trailer is a brand new triple axle and I have had the dealer check the ground, trailer control module etc. I have sat in two of their trucks to test towing the trailer and no issues, however their trucks were a 2014 and 2015 silverado with integrated brake control. I have taken my yukon to my local GMC dealer and they say the cars controller is working fine but they see a C1114 error code. I have talked to another dealer who is closer to where people boat and the first thing they asked is if the trailer had all LED lighting. It does have all LED lighting and he immediately said they are seeing issues for 2021s where there isn't enough current due to the low voltage LED lighting on the trailer and the car then assumes the trailer is disconnected and shuts of the trailer brake control. He also mentioned that GM does not have a fix for this and to speak with a trailer company about possible solutions.

Has anyone else heard of this being an issue on the newer 2021s? I am aware of the potential need to add resistors when using LED on the trailer for this but Im trying to confirm if this is a possible cause of my issue. I might be wrong but based on some searching it seems the car wants a minimum of 55 miliamps current to detect the trailer?

Any info would helpful as Im getting stuck since GMC is saying the car checks out.

One way to test this would be to incorporate a resistor into the trailer wiring.

https://www.etrailer.com/question-71526.html

 

[Tiredmechanic23]

I have a 2021 Yukon Denali wit the max trailering package including the integrated brake controller. Unfortunately Im running into an issue with my electric over hydraulic brakes on my boat trailer. I can't drive the car more than about 100ft before it says check wiring then trailer brakes disconnected. Boat trailer is a brand new triple axle and I have had the dealer check the ground, trailer control module etc. I have sat in two of their trucks to test towing the trailer and no issues, however their trucks were a 2014 and 2015 silverado with integrated brake control. I have taken my yukon to my local GMC dealer and they say the cars controller is working fine but they see a C1114 error code. I have talked to another dealer who is closer to where people boat and the first thing they asked is if the trailer had all LED lighting. It does have all LED lighting and he immediately said they are seeing issues for 2021s where there isn't enough current due to the low voltage LED lighting on the trailer and the car then assumes the trailer is disconnected and shuts of the trailer brake control. He also mentioned that GM does not have a fix for this and to speak with a trailer company about possible solutions.

Has anyone else heard of this being an issue on the newer 2021s? I am aware of the potential need to add resistors when using LED on the trailer for this but Im trying to confirm if this is a possible cause of my issue. I might be wrong but based on some searching it seems the car wants a minimum of 55 miliamps current to detect the trailer?

Any info would helpful as Im getting stuck since GMC is saying the car checks out.

Really? No forward thinking on design to make it work with a trailer running all LEDs... LEDs are common place on trailers now. Hell most semi trailers are running mostly or all LED anymore. I work for a Kubota dealer. Every trailer we sell and have sold in the last few years have been all LED lights.

 

[eshahak]

I had the same issue with my boat trailer with EOH brakes. Does not have led lights. I took a picture while driving ill upload when i can.

 

[Meyersrl]

Wondering if anyone has found a fix for this? I currently seem to get left and right turn signal faults when I first plug in the pigtail, but if I use the left and right turn signal the faults go away. My EOH controller is from Hydrastar and they have a module that supposedly fixes the disconnect issue so I had that installed. Still I get the trailer brakes disconnected but only stop or very low rolling speed.

Its hard to tell whether the light controller or trailer brake controller is disconnecting the trailer. Any way to determine this from the codes?

 

[wayloncle]

My wife's '21 Tahoe does the same thing with our brand new boat trailer with EOH brakes and LED lights. I really think it is the issue of not having enough of a draw for it to sense the trailer is connected.