How to perform ECU coding?
Entering programming mode Ensure the OBD-II vehicle interface is properly connected. Switch the ignition to ON but do not yet start the engine. Choose Detect Vehicle… from the Tools menu, then select Program Engine ECU when the window appears, and click OK. Select Program ENgine ECU to enter programming mode. What happens if ECM is not programmed? When you replaced the ECM, was it programmed with the correct VIN for your vehicle? If it wasn’t, the ECM may not be able to communicate effectively with other parts of your car’s electrical system, which could hinder the starting process.