Brake light not working on one side of van but not bulb, help..

Our 2016 VW T6 van has the rear offside brake light not working, light filament part works, just the actual brake filament not working. So go to change the bulb, weirdly filament looks ok in existing ‘not working’ one, but stick a new correct bulb in anyway but still doesn’t work. All the connections look fine. Why would it not work, anything to check elsewhere? Just odd it’s one side if not the bulb itself.

The van is still under warranty but it’s just a bit of a trek to take over to nearest dealer and lose work time but I’ll give the dealer a call maybe tomorrow and see if any technician there knows too before having to make a trip, but thought I’d just ask here before for any top tips. Cheers

edit, will try a meter on it later with mate to see if power is reaching the connections when brake pressed

Bad earth ?

Wiggle the fitting a bit…

You’ve definitely got it in the right way? Those dual filament bulbs can be put in wrong, although it’s tricky as the pins are offset to avoid this.

I’d try putting the bulb from the working side, which you know is working in the broken side see if the problem follows.

Are you sure you are looking at the correct bulb?

On the pre face lift T5 it’s a combined tail/fog lamp rather than tail/brake. Maybe the T6 is the same?

Not that I spent an afternoon scratching my head about that one, oh no, not me 😯😑😯

duff contact in the holder would be my guess.  Can’t be the earth if one filament is working.  Have a  look at the contacts in the bottom of the bulb holder – I bet one is either bent or corroded

Phil H – correct, yes just figured that out after sodding about for a while, the dual filament one is a tail light/fog light, it was the top little bulb that’s the brake light, bah….

Swapped that and at least fixed now, thanks