Thanks for taking the time to reply!
I didn't actually try to clean the contacts on the receiving element. That's a great point. I had trouble getting my hand in there to get the bulb inserted, but I will give that a try. It looks the plastic housing is melted in part, although I don't think it got ...

I am a recent owner of a 2006 xc70 which is in great shape for its age. Recently the left brake light out went out, and it is reported on the dash. I assumed that the bulb had burned out, but upon pulling out the housing for the bulb, I noticed that one of contacts looked blackened as if from a ...