VIDEOClick to see full answer. Regarding this, does an ECM need to be programmed?Reprogramming your ECM is necessary for keeping your vehicle control software up to date. Much like the operating system on your home computer, improvements in software are often made by your car’s manufacturer. The software can be updated simply by downloading and installing the latest version.Likewise, how do I reset my GM computer? How to Reset the ECM on a Chevy Truck Remove the nut from the negative battery cable using a socket set or wrench. Slide the cable off of the battery and set it aside. Turn the headlight switch to the “On” position to drain the ECM of any remaining power. Wait at least 10 minutes, then turn it back to the “Off” position. Beside above, how much does it cost to reprogram ECM? Pre-Programmed Engine Control Modules ECM Repair costs and labor at a dealership could be anywhere from $1,000 to $2,000 depending on the vehicle. Once the control module is installed then the unit must be programmed to match the vehicle it’s being installed in which requires expensive software and equipment.How do you diagnose a bad ECM? Engine Stalling or Misfiring Erratic engine behavior is another common symptom of a bad or failing ECM. A faulty computer can also be responsible for engine stalling or misfiring, though this tends to be more intermittent. These symptoms may come and go, and may appear to have no pattern to their severity or frequency.