Hello All, I found the problem with my E46 325i. I figured I'd share it. The problem had nothing to do with resistance or bulb base materials, etc.
I had a new neighbor move in Wednesday of last week. I noticed he also had an E46 325i . This morning he came by. We enjoyed a nice pot of Community dark roast coffee, home made biscuits, and lots of car talk. (Yes Honey, we know we bored you with said car talk.) We decided to do some experimenting. We finished the honey covered buttermilk biscuits my wife made and SLOWLY made our way over to his garage. We took the bulb carrier assemblies from both of the tail lights of his car and transferred them into my car. I still experienced the same problem. (Dashboard warning lights showing both tails lights were "out")We put mine in his car, no warning lights came on. Hmmm cue the musical montage and lots of head scratching ensued. I remembered that the trunk lid light assemblies in my car only had a bulb socket for the reverse bulb. The other spot where a bulb could go was completely solid metal. No way could a bulb be put there. (Remember these are the FACTORY BMW Lights and they have NOT been changed.)
We opened the lining on his trunk lid and looked at the light assemblies in there. His had TWO bulbs per assembly. One running light and one reverse light!!! (As you might remember, mine only had the reverse light and the other spot was SOLID metal.) We transferred them from his car into my car. My idiot lights went off!
I carefully examined mine and saw that the rest of the circuits in mine were there for the 2nd bulb. I would be missing some of the parts to hold the bulb in, but for the most part it was there. I figured I had nothing to lose experimenting on mine. Plus it was early afternoon on the 4th of July and I was bored. I mounted the assembly in the vise of my drill press. I progressively drilled out the holes for the bulbs. I finished off the holes with my Dremel tool. I also used the Dremel to cut the notches for the studs on the side of the bulb. I had to use some silver solder to hold the bulbs in place. I didn't want any future problems with resistance etc. I assembled the newly modified parts into my car and they worked like a CHARM! No more idiot lights. Why did the techs from the BMW Dealership not notice this glaring problem? I'm not sure. Two of them looked at the car and neither noticed it.
A little experimentation goes a long way. Then again it could have fried some random part of my electrical system. Please be careful toying with your ride. :-)
Happy Independence Day my friends!
-=Karl North=-