If anything use the SOS isolated flasher. I actually have one I'm going to put up for sale if you want to try it. I also had an 01 325xi and looked into it. The headlights are controlled by the cars bus system. I forget what BMWs is called since it's been years since I've owned it. (CAN BUS Maybe?) But the moral of the story is too many potential computer problems. And the BMW computer system is VERY touchy. I wouldn't recommend trying it. Someone actually created this module called iLights I think it was. There's a video or two on YouTube but it never went into production and the guy would only sell his prototypes to some car show people regardless of amount of cash offered to him. But basically it was able to HLF and TLF using all software and was pnp into the cars bus. Proves that the individual headlights and tail lights are computer controlled individually by the bus.