Morning ,

My series 3 headlights work perfectly well and I have no intention of replacing them , however I do have a question, both headlights have a main heavy duty headlight bulb which also dips , however one of the lamps (passenger) also has a smaller seperate bulb beow the main bulb which comes on when main beam is activated. looking at the other side the bulb isnt missing there just isnt a socket for it , has someone replaced headlight with a earlier/later version

Thanks

Somebody in the past has just chucked whatever in there.
Those headlamp units were in 90% of all cars at one time and are available with or without sidelight bulb fittings.
The s3 has separate side lights of course so the headlight doesn't need that extra fitting.