The ignition timing is set by the electronic ignition timing control system. The input data is processed by the engine control unit (ECM).
Note: It should be borne in mind that in diagnostic systems of the type used on fuel injected engines, when the battery is disconnected, all information stored in the computer will be erased. Therefore, before disconnecting the battery, remove all diatonic information from the computer.
Engine parameters (speed, temperature, etc.) determined by various sensors.