My 97 e36 vert has a tailight out, everything else works. I found the circuit ON the housing was etched and as I messed with it the housing crumbled. Got a different one and it does the same thing. I started tracking where I had power and found that there was no power on that wire. Would you:
a) trace it back to try and find the break
b) run a jumper from the other side where I know I do have power.
The tail lights on those cars brake easily.
I would personally try to follow the wire back, at least give it a shot before pulling power from the other side. Not sure doing that will give you an error on the obc, but that is easily tested.
I have the Bentley if you want me to take pictures of that circuit.
I have the Bentley as well, kept tracing and found and repaired it. Thanks!
What threw me off was that both tail lights were out which shouldn't be possible. One was burnt out and the other wire was broken. All good now