Really long story short... my 2011 Jeep Grand Cherokee 70th edition did not come with a trailer hitch. I added one and the harness to plug in my trailer lights. The Jeep had a factory harness just behind the bumper that matched perfectly to the Hopkins brand aftermarket harness/extension that bolted perfectly to the draw tight hitch. Trailer had running lights but no brake lights or turn signals. I spent a really long time researching what to do. Bottom line... Jeep must turn on the trailer lights function to power up the trailer harness brake/turn signals. Take it to Jeep dealer and they download changes based on your VIN and upload them to your vehicle. Pay them $90. Trailer lights will work then. Pain in the *** and no one knew about it until I contacted a small Jeep dealer in a small town. Hopkins trailer harness did not know about it either but the clue was that they said the 2012 Ford Explorer had to have the programming changed to make their harness "power up". Three Jeep dealers did not know about it. Get the word out and save a bunch of wasted time trying to figure it out.
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