How to test a GMC ignition control module?
How to test a GMC ignition control module? NOTE: Testing the ignition system is a breeze. This tutorial will help you test the ignition coil, ignition module, and the crankshaft position sensor: How To Test The GM Ignition Control Module (1995-2005). How does the GM distributor mounted ignition module work? OK, once the fuel injection computer receives the Distributor Reference Hi Signal, it starts activating the fuel injectors and above 400 RPM, starts to send a 5 Volt Bypass Signal to the ignition control module. It's with the Bypass Signal that the computer starts to retard and advance ignition timing...