The engine electronic control unit monitors the engine operating conditions using signals from the corresponding sensors. Based on these signals, the electronic control unit calculates the required ignition advance angle and sends a control signal to the switch. High voltage is distributed to the spark plugs in accordance with the engine operating order and causes a spark discharge between the spark plug electrodes, which ignites the fuel-air mixture.
Integrated ignition unit (3S-FE, 4S-FE) includes: a commutator, an ignition coil, a spark distributor for the engine cylinders, as well as rotors and inductive coils of the crankshaft angular position sensor and the camshaft angular position sensor. The commutator periodically interrupts the primary current coming from the electronic engine control unit (iGT signal), and thus creates a spark discharge on the spark plugs. In addition, in order to increase the reliability of the ignition system, at the moment of spark formation, information about this (iGF signal) is fed to the electronic engine control unit. The ignition coil consists of a closed core, a primary winding that encloses the core, and a secondary winding that encloses the primary winding. This design allows for the creation of high voltage, capable of causing a powerful spark discharge in the gap between the spark plug electrodes.
The ignition distributor ensures that high voltage is distributed to the spark plugs of each cylinder in accordance with the engine firing order
The inductive coil NE with a magnetoelectric pulse generator allows determining the angular position of the crankshaft, and the inductive coil G - the angular position of the camshaft, which is necessary for the correct determination of the ignition timing.
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