So my buddy has a 2005 BMW 325ci, had a headlight go out so he ordered replacements, put them in, aaaaaand nothing... we switched ballasts, still nothing, got a new ignitor and still nothing... talked to BMW dealer here locally in Dallas, and they were pretty much useless. At this point we are relatively frustrated and so i turn to you nasioc!!! Any constructive replies are welcome and appreciated.

Check fuses and relays? A multimeter will come in handy for this.

is it getting the correct voltage?

is it dropping all of the voltage?

Everything the guys above said. If you have a meter, check for power coming in, and check the ground. Sounds like you are not getting one or the other to the ballast. I doubt there are separate fuses for each headlight, but check them too. If there is no power at the plug(or ground) you will have to work your way up in the wiring to figure out why. Hope this helps

wiring probably.

Exactly what we were afraid if. This will be interesting.

OP any updates on this ?