Probably a simple question but can anyone tell me what this bulb does? I've tried all combinations of lights I can thing of but it never illuminates? I'm taking about the blueish looking one at the top? I'm sure it's a simple solution but I can't think what it might be?

Picture isn't clear - but I suspect that you are referring to a 501 wedge bulb in the headlight. On a vRS this isn't used, as the sidelight / DRL function uses the DRL LED light below.

 

I assume that as the headlights are the same for vRS or non-vRS it is cheaper to populate even vRS headlight with a 501 than have a separate supply line / stock for vRS Octavia.

Sorry about the pic quality - I uploaded a lower resolution version as on my phone but yes I was talking about the blueish bulb at the very top of the headlight. 

 

Good to know it isn't used. I't been bugging me for a while. Was also a bit surprised by the location of the main beam on the inside of the xenons. I guess its not something you see yourself that often. Seems a shame that space isnt used at all.

 

Thanks
D