The block has a memory for the basic duration of injection at various engine speeds and pressures in the intake manifold. The base duration, being read from the memory, is further modified by signals sent from various sensors to obtain the final injection duration.
Other features include:
Engine start control - The fuel mixture must be changed according to different operating modes. For example, at the time of start-up, the mixture should be enriched. Therefore, the injection duration read from the computer memory is specified by signals about the position of the starter, engine speed, coolant temperature, which ensures the supply of additional fuel at the time of engine start.
Injector Control - The ECU controls the duration of injection at different engine speeds and loads.
The Electronic Air Control ECU controls the EACV to provide the idle speed required by the engine and accessories.
Ignition Control - The ECU controls ignition timing based on engine load and RPM, vehicle speed and coolant temperature.
Fuel Pump Control - When the engine is not running but the ignition is on, the fuel pump is disabled to prevent fuel injection.
Fuel cut control - During braking, with the throttle almost completely closed, and when the engine speed is about 13001500 rpm, the power supply to the injectors is interrupted, which increases the efficiency of the engine. The fuel cut function is also activated when the engine speed exceeds the maximum safe value (red line).
Failsafe - If the ECU detects a loss or out of range sensor signal, the computer ignores the defective signal and uses instead "fixed value". This value is not necessarily correct for the immediate situation, but it will allow the engine to run. For example, many ECU decisions are based on coolant temperature. If the refrigerant temperature sensor signal (TW sensor) lost immediately after a cold start, the ECU will use the temperature value "default". This default value is based on the normal temperature of the engine, and therefore the vehicle will be operable until it overheats.
The Backup System - The ECU also checks itself during operation. If deviations occur within the ECU, the system will switch to redundant circuits independent of the processor system. The redundant system outputs fixed values for all inputs and controls the injector accordingly. Vehicle capabilities are reduced to minimum performance.
Self-diagnosis - When something abnormal happens, the ECU turns on the alarm lamp and stores the fault code in an erasable (reprogrammable) memory. The ECU LEDs always display the fault code when the ignition is turned on.