Engine control unit (ECU)

Engine control unit or Electronics Control unit is an electronic device that read the signals coming from various sensors which are placed at different components of car and uses this information to direct those components what to do. It’s more like a brain of vehicle. An ECU is basically made up of hardware and software.ECU is like a computer that communicates with engine and determines almost everything. The primary objective of ECU is to make sure that things are going well in the engine. After receiving the signals from various sensors, its ECU’s responsibility to provide necessary instruction what to do and how to operate for running engine perfectly.ECU directly affects the performance of engine as it helps to enhance the performance of engine.

ECU

Types of ECU

The types of ECU depends upon on what it is being used for and they are differentiated as below

Engine Control Module (ECM)

ECM is also knows aas Engine management system in an IC engine that controls various function like speed control, ignition timing, fuel injection. All these functions are performed after receiving data from various sensors kept at various places.

EBCM – Electronic Brake control module.

This is an ECU that is used in the anti-lock braking system of a car. They were introduced to improve vehicle braking irrespective of the road and its conditions. It is getting more popular nowadays.
The EBCM regulates the braking systems on the basis of signal that it receives from different sensors

1. The Brake: It gives the status of the brake pedal.

2. The four wheel drive: It gives the status whether the vehicle is in the four wheel drive mode.

3. The Ignition: It registers if the ignition key is in place and if engine is running or not.

4. Vehicle Speed: It gives information about the speed of the vehicle.

5. Wheel speed: It gives the information about speed of all wheels of a vehicle

Powertrain control module (PCM)

PCM is an ECU that monitors and controls charging and Automatic Transmission,  speed control, A/C,. The inputs that are fed to the PCM are from:

1. throttle position sensor,
2. output shaft speed sensor,
3. engine speed sensor (CKP)
4. cruise control switches
5. ignition
6. governor pressure sensor.
7. vehicle speed sensor
8. brake switch
9. overdrive switch

Vehicle control module(VCM)

VCM is an ECU that takes care of systems like:

1. Adaptive Cruise control (ACC) systems
2. Electronic Power steering (EPS) systems
3. Electronic Stability Control (ESC) systems
4. Airbag control system (ACS) systems.

The VCM is generally installed in the middle of the car between  the engine compartment and the passenger. They are connected to various kinds of sensors to control various systems in the car. They take information from different sensors to perform better in above systems.

Body control module (BCM)

BCM is an ECU that takes care of wiper control, seating control unit, power windows and door locks in different vehicle.

There are few disadvantages of ECU. As it has complex structure, it is hard to repair. But the feature it gives makes it worth taking risk to have it in your vehicle