Car Electronic Control System

 Engine Control System 

Nowadays, all modern vehicles are 80 to 90% fully equipped with electronically operated devices or components of the cars. It directly controls and monitors by electronic control module/unit ECM/ECU all major components with the help of various inputs devices sensors and switches which data and information provided to the ECM/ECU or Control unit then ECM decision make to the required amount of the form of signal, voltages or command to the several output devices or actuators for the accurate proper operation and functioning to the particular system.

We know all, modern motor vehicles are become sophisticated and better performance plus provide less fuel consumption and emit quite less environmental friendly emissions. These all because of new advanced technology introduced in the last couple of decades, the many parts and components devices are switching from mechanically operated to electronic operates. So that results in the most accurate function and quick response without lack up, Especially Motor Vehicles Engine related electronic operated devices and another electronic operated supporting system.

Electronic means "about electron or electronic " This includes any device operated by electrons. It also includes semiconductor devices such as diodes, integrated circuits (IC) and transistors. Electronic systems follow electricity, Wires must connect the various parts into a complete circuit and voltage must be available. 

There are basic differences between Electrical systems and Electronic systems Electrical system uses electric power to produce heat, lights or motion and to supply electric currents to the circuits for working purposes. Electronic systems in modern motor vehicles used Electronic Control Module ECM also called Electronic Control Unit. This Electronic management unit device is called ECM / ECU with a much greater capability. This system receives signals, process them make decisions and then commands that control other device.

Electronic Control System

The main purpose of an electronic control system is for the safe accurate and proper operation of various components and parts of the vehicles. The main hardware of the electronic controls system includes any device operated by electrons, it consists of semiconductor devices such as diode and transistors. The electronic system follows the rules of electricity, a wire connects the various parts into complete and voltage must be available. The electrical system primarily uses electric power to produce heat light or motion. The electronic control system monitors or controls the engine ignition, fuel, exhaust emissions system, transmission steering, brake suspension and other safety features devices. 

In modern vehicles has three vital electronic operated devices of the electronic control system are Electronic Control Module/ Unit ECM/ECU, (control unit or decision-maker)  the inputs devices are Sensors and the outputs devices actuators devices. 

Electronic control module/Unit 

The electronic control module is a great capability for electronic devices. It receives signals from various inputs devices like sensors or switches and processes them to make decisions and then send a command that controls devices or output actuators.it also commonly called electronic control unit ECU, and other names are a microprocessor, onboard computer, controller. 

The internal components electronic control module (ECM) consists of various small hardware components on a printed control unit (PCU) board with a microcontroller chip and the memory, the diodes, transistors and other devices the make up the chip are often too small to be easily seen. Many thousand are put together to form a single chip. These chips are the basic components of electronic controls. The microprocessor inputs are obtained from various sensors in real-time and also do the calculation and make the decisions to solve a problem quickly often in seconds or less. Microprocessors cannot store information or data. This information or data is stored in an electronic storage device called a memory.

The system computer receives information from sensors and is programmed to operate various system circuits, and actuators based on that information. ECM  serves as the processor or decision-maker in an electronic control system.

Sensors (inputs devices) 

This device keeps track of almost everything no it sends the data to ECM then generates faulty code which is only found using a diagnostic scan tool and also information warning lights blinking on the dashboard or cluster meter.

The most important sensor in your car.

The main essential automobile sensors are:

Position Sensors

• Throttle Position Sensor (TPS)

• Crankshaft Position Sensor 

• Camshaft Position sensor

• Mass Air Flow Sensor (MAF)

Temperature Sensors

• Intake Air Temperature Sensor

• Coolant Temperature Sensor

• Oil Temperature Sensor

• Fuel Temperature Sensor

Pressure Sensors

• Manifold Absolute Pressure Sensor (MAP).

• Fuel Pressure Sensor

• Oil pressure Sensor

• Tyre Pressure Monitoring Sensor (TPMS)

Air Fuel Ratio, Emission and Other

• Oxygen Sensor (O2)

• Nitrogen-Oxide (Nox) Sensor for SCR Catalyst.

• Spark Knock Sensor

Speed Sensors

• Wheel Speed Sensor 

• Vehicles Speed Sensor

Vehicles Safety Features Sensor 

• Hill-start Assist or Hill Hold Control Sensor

• Hill Descent Sensor

• Crash Sensor 

• Cruise Control Sensor

• Reverse Parking Sensor 

Throttle position sensor (TPS)

The throttle position sensor would detect the position of the throttle valve which indicates the angle of the throttle valve. These are transmitted electrical signals to ECM.it also controls the amount of air which calculates the proper air-fuel ratio into the engine intake manifold. The throttle position sensor is mounted into the throttle body. If the TPS sensor is faulty it resulting in high fuel consumption.

Crankshaft position sensor (CKP)

Crankshaft sensor to sense the position and rotation speed of the engine RMP (revolution per minute) of the crankshaft.CKP sensor helps the fuel injection system to make coordinate with the fuel injectors operation and the ignition system. the sensor sends signals for the speed and position of the engine crankshaft.

 Camshaft Position Sensor (CMP)

The camshaft position sensor is one important electronic input device. It is also similar work as the crankshaft position sensor. This sensor detects the camshaft position and speed of the engine camshaft and sends data to the vehicle electronic control module (ECM). Then ECM command to actuator how much fuel enters the combustion chamber and the ignition system provide the spark to the spark plug to ignite the mixture. The camshaft position sensor determines which cylinder is in its power engine stroke relative to in the crankshaft position delivery fuel and spark to start the engine.

If the cam sensor faulty is lit check the engine light. It may cause poor fuel economy, lack of engine performance and in some cases engine will not start if the sensor fully fails. You should not ignore the check engine light which is colouring blinking or displays on the dashboard or cluster meter. Camshaft and crankshaft position sensor has communicated synchronised for the accurate fuel injection system, ignition timing on the vehicles. It directly matters engine power efficiency and reduces the emission of exhaust gases. 

Mass Air Flow Sensor (MAF)

The Mass airflow sensor is one main inputs device of the vehicle fuel injection system.MAF sensor located air filter hose or near air filter housing. The mass airflow sensor detects the amount of air drawn into the engine combustion chamber and calculates the volume and density of the taken by the engine. This result ensures the right amount of fuel is used for optimized operating conditions and delivers optimum combustion and reduces emission levels.

The common failure of MAF sensors are faulty electrical connection, damage measuring element, mechanical damage due to vibration of the accident, clog of the air filter element, drawing much lean under load and engine run rich at the idle of the condition of the engine may also cause of least chance to faulty. warning sign or check engine light on the dashboard/Cluster meter.

Manifold Absolute Pressure (MAP) 

A manifold absolute pressure MAP sensor is mounted on the engine intake manifold. It measures air vacuum pressures inside the intake manifold and indicates the engine load measures the dissimilarity amount manifold pressure. This is important for the engine to be able to adjust the fuel injection based on the change in pressure. The sensor provides instead manifold pressure feed to ECM, that data is used to calculated air density and determine the engine and mass flow rate which in turn determine the required fuel delivery for perfect combustion.

An electronic fuel injected engine may use both mass airflow and manifold absolute pressure sensors. A faulty MAP sensor will affect an engine air-fuel ratio, if the ratio is incorrect ignition inside the engine will occur at an improper time in the combustion. This result in poor drivability and detonation misfire, produce more emission level. Engine rich or lean air-fuel ratio may cause poor fuel economy, slow acceleration and come out a strong smell of fuel ( especially on gasoline).

Intake Air Temperature Sensor (IAT)

This sensor has another important input device of the electronic fuel-injected engine. It is used for measures and detects pinpoint air temperature value that enters the intake manifold. It sense delivery pinpoint air temperature reading that means optimal fuel delivery and maximum performance.

The inaccurate or faulty air temperature reading can have a direct effect on engine performance and poor drivability. In such an abnormal condition check engine light will be displayed on the dashboard. 

Engine Coolant Temperature Sensor (ECT)

Engine coolant temperature sensor has work to detect the temperature of the engine coolant which circulates engine cylinder head and block. It is a kind of thermistor that changes resistance with temperature and operates using electrical resistance to measure the temperature of the coolant. It detects that the engine temperature is too high and protects the engine from possible damage due to overheating. The sensor sends signals to ECM then it verifies the engine timing and fuel calculation for optimal engine performance and it always maintained the working engine temperature.

If the engine temperature is high on coolant it quickly translates into engine performance it may be a major issue due to overheating, in such a case ECM send a signal to check the engine light and a warning light appears on the dashboard. when the engine overheating either it is leakage of coolant or lack of coolant level if ignore overheat engine become sluggish and has poor engine performance.

Oxygen Sensor (O2)

The oxygen sensor or O2 sensor is installed downstream of the exhaust manifold or exhaust pipe.O2 sensor measures the amount of oxygen in the exhaust gas and monitors the burning efficiency which the air-fuel ratio is either lean or rich. Oxygen sensors work by producing their voltage when they get hot 600°F on the tip of the oxygen sensor when the engine is cold will not produce a voltage signal. Whatever detect report this feedback to ECM which will calculate the optimum air-fuel ratio to keep the engine running a good efficiency and power. 

Oxygen sensor (O2) plays a vital role in engine performance, fuel efficiency and emission level. A faulty oxygen sensor will cause the vehicle to idle and jerk as well as cause high fuel consumption and lack of engine outputs performance.

Knock Sensor

The knock sensor is located is to the outside of the engine block it detects vibration or knocking noise that occurs on irregular combustion of the engine. That knocking noise monitor and convert the electrical voltage signals feedback to electronic control module ECM. Then ECM judges the information and determines ignition timing adjust to correct the knock for the irregular combination or detonation occur in the engine. 

Knocking noise occurs in multiple causes they are most common causes are an improper air-fuel mixture (means lean or rich mixture ).poor ignition timing, faulty /defective spark plugs, carbon deposit on the engine cylinders. 

Vehicle Speed Sensor (VSS)

Vehicle speed sensor VSS is mounted on the output shaft of transmission and transaxle, It is one kind of speed sensor that detects how fast your vehicle running or driven and measuring the rotation of the transmission or transaxle output shaft as well as wheel speed also monitors. This sensor helps with multiple components ABS, reading of speedometer operation, odometer and the rate at which crankshaft spinning. VSS sensor determines of automatic transmission

 shifting method or torque management of the transmission and transaxle. This all gathers input from the sensor then report feed to ECM. The vehicle speed sensor has a toothed ring that voltage generates which provide constant voltages signals to the control unit.

A fault or failure vehicle speed sensor directly affect multiple speed-related components firstly malfunction of the speedometer and odometer, in automatic transmission facing trouble gear shafting because of lack of torque converter, improper activation of Antilock braking system (ABS), ineffective cruise control, power steering and other systems.

TYRES PRESSURE MONITORING SENSOR [TPMS]

TPMS system is one of the important safety features of all modern vehicles. This system performs electronics and monitors the air pressure in pneumatic tyres. It also provides information to the driver on all tyre pressure through an instrumental cluster meter.