Trailer turn lamp faults but no trailer connected

[JRMan]

I have a 2017 Expedition Platinum 4x4 with the type 3 instrument cluster. I am getting a trailer turn lamp fault and I don't have a trailer connected to the vehicle. I haven't owned this very long so not much history with the vehicle. When I was looking at the vehicle before the purchased I noticed that the 4 pin connector for the trailer hook up was corroded and I had the dealer replace it as part of the purchase agreement. I drove it before purchasing it and after purchasing and the fault wasn't showing up. Once the 4 pin connector was replaced (about 3 weeks after purchase) the fault showed up. The old 4 pin connector didn't have led lights on it (to the best of my memory) but the new 4 pin connector does have led lights on the plug. Do you think these led lights are messing with the system to cause the faults? See images below.

 

[bodabdan]

I'm not impressed by the quality of that installation.
For the LED's to be a factor they would have to be grounded. It's possible that the plug has some internal connections to make that happen. If any of the LED's light up without a trailer connected then it's absolutely a suspect. Turn on your flashers and parking lights and see if anything lights up. If so, there is an internal circuit and likely your culprit.
Have you connected a trailer to it to see what happens?

 

[JRMan]

I wasn't happy with what their work either and I didn't want them messing with again after seeing their work. I did put on a turn signal and the corresponding led did light up. I am going to replace the plug with one that doesn't have led's on it and replace the bracket that they cut. It might be a little bit before I can do it, but I will let you know the outcome. I haven't had a chance to connect my trailer yet. Thanks for the help.

 

[mr_dave]

Yeah, I'd be willing to bet those LEDs are the culprit. Also, that bracket wasn't cut, that's what it looks like. The 4pin receptacle clips into that.

 

[Timo2824]

Cheap auto parts store part, I'm assuming the dealership wasn't a Ford Franchise? I'd go to your favorite Ford parts house/website and put a factory plug back on it. It'll push up into that bracket and look cleaner as well as not give you a fault code.

 

[JRMan]

Well dang, I assumed they had cut the bracket. You know what they say about assuming... I had already ordered a bracket and plug (without LED's) replacements for it, so I installed both. I actually left the factory bracket in place and installed the aftermarket bracket to the rear of it. This pushed the bracket back just a little bit and makes it a little easier to get to but is still behind the bumper. With the new plug installed it isn't giving me anymore faults. Yahoo. Thanks for everyone's help.