Q: How Does Your ECU Use Sensor Data?

asked by on November 18, 2015

How does your ECU use sensor data?

Today’s modern vehicles are made up of anywhere from one to seven computers that assist with the car’s day to day functions. An engine control unit (ECU), is a computer that similar to that of a laptop or smartphone in terms of responsibility. The ECU has the important job of processing all of the data that is sent by the sensors throughout the vehicle. It “uses” the sensor data that is being sent to help read the messages revealed by the vehicle on its current status. Different sensors perform different operations, therefore the software in the ECU has to be able to process all of the different information from the variety of sensors and not only determine what each sensor is doing but also respond accordingly.

One such sensor that the ECU helps to monitor is the Mass Air Flow sensor. While the engine is running, the ECU uses this sensor to read how much air is entering the engine. At the same time the ECU is also reading the position of the gas pedal through the throttle position sensor. While this is going on, the oxygen sensor takes readings from the exhaust gases to determine how much fuel to add with the fuel injectors into the combustion chamber. The ECU uses the camshaft and crankshaft position sensors to determine where the pistons and valves in the engine are at any given time.

The ECU uses all of this information to start and keep the engine running. Quite a task for these computers to handle. It is important to keep up with routine maintenance to ensure that all of the ECUs and the sensors continue to work in harmony together and keep the vehicle running efficiently and safely.

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