7.2. Electronic control system of ignition (and injection) petrol engines
General information, description of the principles of functioning and precautionary measure
The system of ignition of the petrol engine is integrated with system of injection of fuel and is run by the uniform block of electronic control of ECM (see the Head of the Power supply system, release and decrease in toxicity of the fulfilled gases). The system of ignition consists of the module of engine management (ECM), the switch of ignition, the module of ignition (ICM) with the built-in coils, spark plugs, high-voltage wires and a set of information sensors.
On C14NZ engines the system of ignition consists of the CKP sensor, the distributor with a rotor, coils of ignition and spark plugs. All elements of system of ignition are adjusted and provide lack of shift of the moment of ignition.
Other petrol engines are equipped with system of direct injection (DIS). In this system there is no ignition distributor. Distribution of tension of ignition on separate cylinders is made by electronic elements. Tension necessary for formation of a spark is created by two coils of ignition which are fixed in the module of ignition of DIS located on a head of cylinders. Synchronization of system of ignition is carried out by signals from the CKP sensor. The CKP sensor is sideways on the block of cylinders. It registers the speed of a bent shaft by means of the gear rotor established on a pulley of a bent shaft.
For definition of the moment of ignition the control unit uses the characteristic of ignition put in his electronic memory defining the optimum moment of ignition in various service conditions.
In electronic system of ignition, very high voltage is generated! Be attentive, observe all necessary precautionary measures at service of any components of system, including not only the main (the ignition module, the coil and VV of a wire), but also and accompanying, such as candle sockets, tachometer and other equipment. Persons with the implanted pacemaker of ignition should not be allowed to service of components of system!
In order to avoid damage of components of system of ignition, and also for the purpose of decrease in risk of getting injured, observe the following precautionary measures.
- If the engine is not started, do not hold ignition included more than 10 seconds;
- Before a detachment of an electrical wiring of any of components of system switch off ignition;
- Before connection and a detachment of the diagnostic equipment (for example, a stroboscope) switch off ignition;
- Do not allow grounding of windings of the coil of ignition on weight.