What Exactly Is A PCM And What Does It Do?

Technology has taken over nearly aspect of our lives, even in our cars. The cars today have computers that help maintain better control over the car. One of the computers that are used in cars today is called the pcm computer, or powertrain control module.

The specific purpose behind the pcm in a vehicle is to help the driver control the vehicle in any kind of driving condition. If the driver is on wet or icy roads or on a dirt road the sensors on the car will send signals back to the pcm which will in turn send signals to various parts of the drive train to perform in a certain way to help the car remain in control.

So the way that a pcm works is it has sensors in certain locations throughout the powertrain. The sensors will sense when traction is being lost and will relay that to the pcm computer. The pcm computer then relays back to components of the powertrain which then behave according to instructions sent by the pcm. One example of this would be the axels in the car. They can turn at different speeds causing a certain tire to spin quicker or slower that can then result in more control under slippery conditions.

The braking system is another area that the pcm has some control. Brakes can make a big difference in how a car handles on an icy or slippery road. One thing that causes problems is when someone locks up the brakes. All control is lost at that point. The pcm computer is designed to make sure that this does not happen, under normal heavy braking. It can do this by pulsing them. It can also adjust how much pressure is applied to each brake to help make sure that the car is braking in a straight line or whichever direction the driver is steering the car.

The transmission is another part of the powertrain that the pcm can control. There are sensors in the transmission designed to relay information about its performance back to the pcm. The power that is passed from the engine to the transmission can be regulated to help maintain control of the vehicle in varying road conditions, such as a steep climb in the mountains.

As car parts tend to do, the pcm is also subject to breaking or wearing out. It is best to have it fixed as soon as you can after this happens if it does. The car will not handle the same and can actually become a safety hazard to you and anyone in the car with you.

No matter if you buy a used pcm yourself or have an auto mechanic shop buy a new one; you should let the professionals install it for you. While it is not terribly difficult for those who understand what they are doing, it is possible for wires to be hooked up incorrectly which will cause further trouble.

The pcm is not the only computer on board. The ecm, or engine control module, controls aspects relating to the engine of the car. It controls things like fuel and air flow and spark to maximize the balance between efficiency and power. The improvement of performance, efficiency and safety are the driving factors that have led to the use of computers in our cars.