Neuk_
Honorary Master
Speaking of lights - I also do replace rear brake lights on my 'Rolla, but the hazard/reverse lights are still stock.
Front headlights I replaced with newer ones.
Broken lights can also be caused by dry solder joints or the filaments breaking from the vibration of the boot lid closing.
I had a most irritating one with our Sharan. Left rear indicator stopped working. Opened the cluster, light works. Put it back, it works. After a while it ^#%#^ stop working.
In desperation I replaced it with a new bulb, and the problem went away.
The Sharan, what bulb was in there and what bulb did you replace it with? Depending on the year, that sounds like a resistance issue with the CANBUS.

