It was a Diagram Posted by someone else that I copied. But, it looks like it is from the Mercedes Manual.
I don't have the site but if you regester with the Mercedes EPC you can look at the Manual for free.
Mercedes also sold the Manual on CD.
Part numbers for service Manuals STARTEK
Star Service CDs and DVDs
Contact Consumer Promotions at 1-800-FOR-MERCedes for current pricing and ordering information on the accompanying CDs and DVDs that are available for purchase.
Please note you need to pay attention to what Computer Operating System the CD will Work on.