2011-2018 BMW 3-Series Auxiliary Turn Signal Indicator Lamp Replacement

Gently use a car trim tool to pop the mirror glass off its central holder. You shouldn't need to detach the cables to it, as it can just rest against the window after removal.

There are three plastic clips holding the front wing mirror trim in place. Squeeze the plastic 'legs' of the clips to release and then push forward. With a little bit of persuasion, you should then be able to slide the plastic cover off.

Use a T10 Torx driver to remove the three T10 Torx screws along the bottom of the inside of the wing mirror, to loosen the bottom of the wing mirror casing.

Loosen the bottom half of the wing mirror, and slide the indicator lamp unit out. With a litte bit of persuasion, the cable connect should just pull out. Replace the old indicator with your new one, and reconnect the cable.