Right Back Taillight Ground- FIXED!

[hambler]

I was driving home the other day when my 2001 540i informed me I should check my brake lights and back up lights, and I also noticed my right turn signal not blinking at the correct speed. I suspected a ground problem with so many problems at once, and a quick wiggle of the brown ground wire made the light flicker confirming my suspicions. What I was not expecting was to pull the plug and find the male ground contact to just be gone- along with some melted plastic around it. (BMW uses brown as a ground wire, and in this case is the #3 terminal in the connector) A quick search of the forums and I discovered this seems to be a common problem on e46's, e39's, and e53's. There are several suggested fixes out there, but nothing I liked so I came up with my own solution that worked quite well.

I apologize that all these pictures are rotated 90 degrees for some reason, but here are the burned/melted connectors.
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First I removed the taillight from the car, and marked out my cut line. I used a 3/16 female blade connector, so I marked out a 3/16" tab and a square end.
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Next, using a dremel and a small cutoff wheel I made the cut and bent the tab slightly to give better access.
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I then made a small jumper lead with a 3/16" female blade terminal on one side, and a 1/4" ring terminal on the other. I made my wire slightly too long, ideally it would have been 1/4" shorter than mine.
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Next, I took small die grinder with a sanding pad and removed the paint around this mounting hole on the car body so my ring terminal made a good ground. I don't love this part of my solution, ideally I would have had an external starlock washer to bite through the paint so I didn't need to do this. I didn't have one however, and the paint is not original on this car so I didn't mind sanding a little bit away behind the taillight seal. It won't let me attach any more pictures, so I guess this last step you are on your own. I then reinstalled the taillight, and used an ohm meter to verify that I had a good ground on that mounting stud. Plugged the taillight back in, and a quick check of the lights showed that I had fixed the problem! All hidden away where you can't see it, no ugly ground wire directly to the battery, and I didn't have to tamper with the factory wiring in case BMW ever issues a recall for this problem. Hope this helps someone out there, it's my first time doing a write-up so please leave some feedback.

[Mindaugas45]

The photo's make's it much better thank you, i'll keep you'r guide in mind, you never know when the same problem will occur.