I have been told that this part rarely fails by both the dealer and a MB indy shop here in Phoenix AZ so I picked up another alt sensor from a salvage yard last year. It was okay for awhile but as soon as the temp here in AZ got hot ; the "check engine" light came on again. Thank-you for your reply; I just wanted to verify the code since "eight flashes" is the code for a coolant sensor in some of the other models. Any other ideas? Tom