Electronic Control Unit (ECU)

What does a car's electronic control unit do?

An Electronic Control Unit (ECU) controls the electrical systems in a car. There are lots of ECUs in a car, responsible for the engine, gearbox, brakes, suspension and every other electronic system (almost everything in a modern car is electronic). Altogether, these systems are sometimes referred to as the car's ‘computer’ – although a car doesn’t, strictly speaking, have a single computer in control, just lots of different ones.