The ignition timing (ignition angle) is determined by the DME control module on the basis of the engine speed and load signals and output via the ignition output stages. This procedure also takes into account other input signals such as the engine temperature, intake air temperature, throttle valve position and signals from the electronic throttle control EML, dynamic stability control DSC and adaptive transmission control AGS.
The engine speed and battery or system voltage are decisive with regard to the time available to build up the primary voltage in the ignition coil. From these variables, the digital motor electronics then determines the necessary dwell angle thus ensuring adequate ignition voltage under all operating conditions.