I have a Chevrolet S-10, according to the the Ignition System Circuit Diagram the ICM gets an Ignition Control Signal from the PCM and sends a Switching Signal to the ignition coil.
As the Ignition Control Signal from the PCM is just and on/off signal and given that the ICM does not get any other signals I'm wondering what the ICM does? What is needed for? Why can't the coil get the signal directly from the PCM?
What would happen if I connect the PCM signal cable directly to the coils switching signal terminal?