Modern vehicles can contain around 100 Electronic Control Units (ECUs). An ECU is a minicomputer that collects data and determines whether to activate a function based on the information received.

What is an ECU? ECU stands for Electronic Control Unit – basically a computer that handles various functions in your car.

The powertrain control module isn't the only computer that you can find on contemporary cars, but it is the primary computer that controls most systems and functions for vehicles that utilize a PCM.

In semi-automated driving (SAE levels 2 and 3), the driver must be ready to take control of the vehicle at any time.