I have an '86 mk2 golf that has just failed it's MOT due to a driver side brake light not working. I thought this would be a quick fix of replacing the bulb but after swapping the bulbs over to test them it turns out the bulb is fine. It's not a fuse problem as the passenger brake light works fine so I was just wondering if anyone else has come across this or has any ideas what else it could be or things i can test to determine where the problem is?
Might be something simple like a corroded bulb holder, try cleaning up the contacts with some wet and dry/emery cloth. If not then must be a wiring fault, which will involve tracing wire back to fusebox to try and find a break.
