my 2000 mercedes w215 CL500 ...308000 miles , lights on driver side uk have all failed ..the bulbs are good .....how can I check wires and is there a separate fuse , front passenger left side is fine and all rear lights good including mirror indicators ..any help would be greatly appreciated

Hello Matthew, I have 2004 215 CL with similar problem except that it affects RH rear light.
I too am lost on this one now. I understand the power comes from the rear Sam via a relay.
If you have not resolved your problem yet I am willing to work with you ??

Failing that, could anyone help please ?

I'm under impression that door lights are controlled by door module, at least in newer cars they are...

Thank you, I will check that out. Certainly grateful for your reply.

I have several live codes all relating to the rear light module itself via the rear SAM --- B1615, B1516,B1620 B1623. in module E4.
I checked the drivers door side module but no reference to rear lights.
Older posts here refer to water ingress with flooding in the boot itself & damage to Rear SAM
but there have been M-B alterations to the 2004/5 models (Mine is 2004 model) & I believe the SAM is now buried under rear seat

I removed the rear light complete. There was contamination in the lower area. Everything cleaned up & bulb holders too.
Secondhand (Later) rear light modules are extremely hard to locate ! So will continue to search & diagnose.

Any thoughts or experience on this perhaps ?