Recently when I cold start my E60 the left headlight is purple on startup then quickly warms up to the correct color (8000k). After the first cold start its fine and no more purple. I can turn it on as many times as I want and it does not start up purple, only during cold start its purple.

I doubt its the bulb because after its warmed up its the same color as it was before and the same brightness. Its just purple on the first cold start and then its fine lol. What is the problem do you think?

 

There's no problem. The bulb just color shifts. It's a "feature" for some bulbs.

There are bulbs that do not color shift at all as well.

 

Thanks Simon. It just started happening which is what got my confused haha.

 

And the color shifting it's ONLY because the bulb. The drosser has no effect on it.
Usually, the purple/pink color of the bulb is a sign of his ending life.
Hopefully it's not your case.

 

Good reminder. Yes, that is true. I didn't realize purple was as well, but pink is an indicator that it's crapping out.