The PCM of a vehicle is the brains behind the power. It is an electric circuit board that operates everything from the car radio and air conditioning to the transmission and fuel delivery. When the PCM (Powertrain Control Module) is not working properly, the vehicle will have problems such as warning lights displaying on the dashboard or even stalling and sputtering. Resetting the PCM on your vehicle will help to clear all codes from it after a problem is fixed.
Open the bonnet of the vehicle.
Disconnect the negative battery cable from the battery. Use a wrench to loosen the locknut, and pull the cable off. This cuts the power to the PCM.
Wait for five minutes. Reconnect the negative battery cable to the battery and close the bonnet of the vehicle. The PCM is now reset.