What is a powertrain control module?

Answer 1

The pcm is the computer that controls all of the engine functions and sometimes the transmission.

In a vehicle, the term drivetrain or powertrain refers to the group of components that generate power and deliver it to the road surface, water, or air. This includes the engine, transmission, driveshafts, differentials, and the final drive (drive wheels, caterpillar track, propeller, etc). Sometimes "powertrain" is used to refer to simply the engine and transmission, including the other components only if they are integral to the transmission.

A vehicle's driveline consists of the parts of the drivetrain excluding the engine and transmission. It is the portion of a vehicle, after the transmission, that changes depending on whether a vehicle is front wheel drive, four wheel drive, or rear wheel drive.