Bariukas

My girlfriend has 2003 Audi A4 1.8T with Xenon headlights.
Drivers side xenon stopped working. I changes the bulb from passengers side to drivers side and its not working again.
SO i put drivers side xenon bulb into passengers side and it works fine.
What can be the problem?
Additional info:
It has DS1 bulb inside.
Its mono xenon light.
Everything else: like long lights and turn signal works fine.
I Also noticed that reflector on the drivers side headlight is silver and on the passengers side is black/gray plastic.
My guess is that the car was in small accident or something and they changed one headlight. Thats why they are different.
Despite all those differences the headlights were working fine before.
Thank You.

JG-NY

probably the ballast, you could swap ballasts between housings to confirm...

Bariukas

Is hard to swap it?
How much does it cost?
What makes it to go bad?

Merkin

have to pull and remove the ballast thats mounted to it

JG-NY

there are 6 torx screws that hold it in housing.
if you swap ballasts with other side and it doesn't work, you know its ballast.

also, you can get ballasts on ebay for 90 USD.
you can use a 5G ballast or a 5GL ballast for 2003 A4.