Panda 2 headlight driver side dark, need help!

Tach together, I usually get on with the people in the Polo Forum, but you certainly help me, too? So I have the following problem: A well-known one of me has a Fiat Panda 2, year of construction and motorization I don’t know now, I don’t think that also doesn’t matter, if it does, I still ask! So, now to the problem: His dipped light on the driver’s side does not work, the passenger side goes and the main light also! Now comes on: On the stick r on the driver’s side there is tension, and if I switch the bulbs from the driver’s side to the passenger side they also work. So I was there with my Latin at the end because there is between white (that’s probably mass) and yellow (that’s probably the switched plus) voltage (so 11,8V) and the bulbs work on the passenger side. Does anyone have an idea? MFG CP