Door frame Grounds?

Hi, I ran some LED strips on all 4 of my doors of my 2010 Ford Escape.Basically to create puddle lights. Everything done nice and neat. All the power wires lead to the door trigger which is located under the center console at the smart junction box. Anyway, I didn't want to run double wires through all the doors into the car for a ground and power. Instead I created ground points on all the door frames. I have ran into an issue which is the front passenger and driver side doors strips dim when moving the doors back and forth. The back doors don't do this at all. I thought at first I may have a pinched wire issue or bad LED strips. After searching everything over the wiring is clean and connected properly. I have been going over in my head for possible issues that could cause this, then something hit me. The doors are prolly not my best bet for a ground. I believe what is happening is the ground is getting weak as the door moves back and forth on the hinges. Am I right with this assumption and if so, couldn't I just located maybe the negative wire for the power mirrors and use that for the ground? I was also thinking of grounding the doors with heavy wire like 10 gauge or bigger from the door to the body of the car. Any help would be great. Its very difficult getting the wire through the rubber wire protector that connects from the body of the car to the side of the doors. I'm trying to avoid having to run more wire through them. Thank You in advance!

THere may or may not be a ground wire on the mirrors. They operate on reverse polarity. If they are reverse polarity rest at ground it may work.   Running a wire from the door to the chassis will work.

Sorry I have not got back to this post, been hectic lately. I have went with the route of grounding the doors. I used 10 gauge wiring and grounded all 4 doors to the body of the car. Thank you for your help!

Just a few shots of how I grounded the doors. What you see here is pretty much identical for the opposite doors

Totally pointless if you have a constant ground at the window switch or door module, also those screwheads will rust out pretty quickly.

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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
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