I just bought a salvageable 2003 E320 CDI, the diesel version, and the cooling fan is not working. I also have a 2003 E320 gasoline model but don't know if the cooling fan is the same for both vehicles. I have the damaged unit and it has a circuit board attached to the shroud. I don't know if it's the fan motor itself that is bad or that circuit board. It shows signs of attempted repairs but I prefer to find an original fan but I have no idea what the electronic box attachment is called or what is its function! Any help?