What Are the Symptoms of a Bad PCM?

A bad PCM, or power train control module, has a check engine light that does not turn off, an assortment of random codes, intermediate stalling issues and poor engine performance. The power train control module monitors the drive train system.

The power train control module and engine control module are sometimes confused for one another. The engine control module monitors the sensors found on the motor while the power train control module handles the drive train sensors.

A vehicle with a failing power train control module will not correctly interpret the readings from the engine’s sensors. This results in the vehicle running rough with fuel cutoffs, accessory power failures and ignition issues. To repair a damaged power train control module, replace the unit.