got the dash message few weeks ago "L. turn sig. rflctr"
i searched all the W220 threads for solution, most have suggested to replace the LED or in case not solved, replace the DCM (cost arround 200 Euros used) if you could find the one with the same reference!!!.
using my experience in circuit boards design,i could fine the solution and here i share it with you
the DCM goes to shot mode for the LED light and when checking the fault code using STAR the fault code is "Lamp short circuit"
the same LED works if connected to the other side DCM!
the solution is to replace the damaged transistor in the DCM board that control the current to the LED lamp.
see the photos about how to open the control module and replace the damaged transistor.
you can find threads about "#W220 door panel removal" in these forums.
Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.
