What is the ECU/what does it do?

The term ECU (Electronic Control Unit) is a universal name given to a variety of electronic control systems found in a car. Collectively they make up the car's computer or brain which controls and regulates key components of the vehicle.

Getting into the details of the ECU

ECU’s are located within the dashboard or engine bay. It is often possible to ‘read’ or interrogate your car's various ECU’s using a laptop computer with relevant software and cable or a dedicated reader via a connection port which is usually located in the dashboard. This method is used by mechanics for diagnosis of certain vehicle faults.

An ECU controls or governs aspects of a car's systems including, but not limited to, the engine, ABS, suspension, automatic gearbox and power steering.

What if something goes wrong with the ECU?

Like any electronic component an ECU can fail for a number of reasons including short circuits, dry solder joints, water damage or age. Diagnosis is generally much easier with the correct reader which can be used to obtain error codes from ECU.