[jesseUSA]

Hi,
I have BMW328i.
My low beam light is malfunctioning.
It seems that the former owner replaced all the bulbs and the connectors tin order to have white light.
After a while I could find the right replacement bulb (see pic with the right connector), but when replacing it, it is still not working.
Any idea what am I doing wrong or can be the problem?


Thanks!!!

[Billfitz]

If the new bulb doesn't work then it's probably not the bulb. Since that's a HID bulb the next thing to check is the ballast.

[jesseUSA]

But the ballast is for all the beams together no? the other bulbs work well.
I was wondering whether I'm doing something wrong with connecting it

[Billfitz]

The ballast may be different for each bulb, especially if it's not OEM. In any event if it's not the bulb it's something between it and the FEM, so you have to trace it all the way back to there. The first thing I'd do is check for voltage at the connector to the bulb.

[jesseUSA]

Sorry for the silly question but do I have to use the ballast? I know that it was added after market, my question is was it originally included a ballast or it was added after market?
Wondering maybe it would be easier to replace back to the original set up

[Billfitz]

Judging by the base he converted from H7 halogen to HID. HID bulbs require a ballast. The last thing I'd do is to go back to halogen. When I got rid of my halogen I considered HID but went with LED instead, in part because LED doesn't require a ballast.