Starter Control Function

If the SCCM detects the "engine start" ignition key position, it sends a CAN message to the ECM to actuate the starter. After receiving this message, the ECM sends another bus message to the UEC via the SCCM interface. The UEC then actuates the starter relay incorporated in it. Direct actuation of the start relay by the SCCM without the "diversion" via the ECM would not be sensible as the ECM decides whether the starter should be actuated (if the engine is already running, the ECM will not send a bus message to the UEC to actuate the starter, even if the driver has turned the key to the "Start" position).