Thank you for the post and offering to help.
its the headlight on the drivers side but also the backlight on the drivers side sometimes. 2 garages seem to think its the bcm though.
Im not sure what the mercedes codes are and doubt if the garage would give them to me as they were not very helpful. Is that the technical name for them?
thank you again for your post. I wont be back home for a few days so unable to send pics straight away.