Originally Posted by mark///m3

So I recently purchased my second 4.6is and it came with bad taillights just like my previous one. (Sold my last one missed it blah blah blah)

Anyway I did not want to buy my third and forth BMW taillight assemblies so I did some digging. I came up with a taillight bulb and harness made by Mercedes for the same exact problem. It completely takes the circuit board out of play and hardwires a new bulb socket to the brake wire and ground wire. I installed it flawlessly and and have two functional brake lights again! The best part is the kits from Mercedes totaled about $40 for both sides, $20 a kit.

Here is the part number, you will need two kits 164-826-00-07.

Simply wire in the red wire to the brake light feed wire and the brown to ground. Install the twist bulb holder in the taillight just like you removed the factory one and done!

Enjoy your fixed once and forever taillights and enjoy the savings!