[Mfennell]

I am trying to install a Curt Spectrum brake controller on my 2021 Yukon Denali. I am unable to locate where the factory supplied pig tail plugs in.

 

[Riorider]

I'm having the same difficulty (locating the port where the pigtail plugs in). I have a call in to my local dealer and they are going to help me find it. I'll post here where it is. I've looked with a mirror and flashlight and cannot see it - or feel it.

 

[Riorider]

I am trying to install a Curt Spectrum brake controller on my 2021 Yukon Denali. I am unable to locate where the factory supplied pig tail plugs in.

AND the answer is... there are two versions from the factory - one has the pigtail, and one does not. Mine does not, and apparently yours does not either. There are bare (?) wires (6 of them) with about 8" free up under the dash behind / above the "module" per the technicians at my dealer. So - I'll have to schedule it in next week to get them to wire those 6 into the connector, another connector, or direct to my 4 wire controller (mine is Tekonsha's Prodigy" wires.

They told me the suffix that identifies whether your Tahoe (this is 2021 only) has the pigtail from the factory or not, but I don't recall. So - for prospective owners check first. I wish I'd noticed that mine didn't have the integrated brake controller but with so few cars available at the moment I suspect I would have taken this one anyway.

I do very much wish they'd updated the owner instructions and NOT placed the sheet and the pigtail in the glovebox, making me go look for a couple of hours and then taking it to the dealer for them to look for an hour...

 

[Djzscuba2]

Yes, sad but true, for the 2021 Chey Tahoe, there is no female plug for the brake controller. Per the below pictures, you have to remove the top panels, and find the loose wires. (The diagram GM gives you, and the male adapter are completely useless). At least you know.

 

[Djzscuba2]

Just an update. The dealership charged me $180.00 to wire in the harness for labor. I have since had numerous calls with GM to be reimbursed, but they won't. Stated they don't pay for Labor. I explained that the vehicle came with a tow package, they supplied the female adapter and had instructions on how to plug it in! But, there was no plug from the factory. But, again, as of now, GM is refusing to help.