Volvo Repair: Rear tailight and door lock on 92 960 Wagon, worst case scenario, weird behavior

Question
I have a 92 960 Wagon with two issues:
1. Rear brake tailight- The lens had a bad seal and the housing got wet- since that point brake light malfunctions. I can get it to work by turning it to certain positions but then all lights will flicker on and off when running lights are on among other weird behavior. I think it may be the bulb socket but have been told it may the monitor.

2. During a recent bout of cold weather the driver's side door lock became hard to turn. I assumed it may be frozen but now that it has warmed up, the key will not turn the lock at all.

Any ideas on how to fix these issues would be appreciated.
Francis Mackey

Answer
the lens housing that contains the power strip is probably corroded, worst case scenario you will have to replace that tail light.

as to the door lock being inoperative, id have to remove it, and inspect the door. it sounds like something physically is wrong.