After some digging on the Net, I now understand what a SAM unit is on the later model Mercedes. Apparently a faulty one was the cause of my battery drain the first time around, and the cause of my neighbour's dash flashing all sorts of issues.... Helmet will know all about this. They sit beneath the various fuse boxes and control what the driver commands . At $1800 each and not an uncommon problem ( a failing battery can upset them via voltage surges to their processor ). is not for...