Hey guys, I have this weird issue happening on my LHS: sometimes, the rear driver's side rear turn signal won't blink. It acts like a burnt-out blub, but usually a simple tap of the cover and it works again. I have replaced the blub twice, but the issue remains. The wiring looks OK, but honestly I wouldn't know what to look for there. It seems to happen more when it's cold outside, or there's been some kind of precipitation. Again, this would lead me to think wiring, but it still has its sheathing.
Any ideas would be super appreciated.

