Originally Posted by zeezz
Quick update since this is still bothering me. I actually took a video of my rear turn signals and determined that the flicker happens once every 4.5 minutes (an odd timing).. I don't THINK there is anything in between those 4.5 minutes (I checked the 30/60 second intervals). I left a video running for 20 minutes and noted there was a flicker at every 4.5 minute interval.
In reading some older E90 threads, I'm thinking this is the check the system does to see if the bulb is burnt out. Since LEDs light up instantly vs incandescents (which wouldn't even light to a significant amount on that pulse), we get the flicker.
I guess I'll do some more looking in the coding section, and/or figure out what else to do. I guess a flicker every 5 minutes is not that bad, although at night it is somewhat visible.
I am 99% sure the flicker has been fixed by coding off warm/cold checks. I would get a bunch of quick flashes right on starting the car, and now that is gone. I'll have my friends keep an eye out next time to see if the 5 minute flashes are still there. Refer to the coding thread for more details, this should work for any of our bulbs