SAM = Signal Acquisition & Actuation Module
The SAM controls the wipers, starting, horn, central locking, lights,
tacho readout, immobiliser, electric windows, electric roof opening...
in fact, pretty much all the non-engine electrics.
Oh, and all the SAM's that JJ mentions were for ForTwo's and Roadsters,
none for a ForFour....as none have needed 'saving' as yet !