The Ramjet is supplied with its own code reader to diagnose any problems that may crop up with any of the sensors or the computerjust like a modern car! The code reader is also used to set the initial base timing by plugging it into the connector with the switch in the Off position, starting the engine, and switching it to On. This puts the computer in timing mode. Now you can set the advance (10 degrees BTDC) at the crank with a timing light just like a carbureted engine. The Ramjet can also be synced up to a GM Tech 1 scanner or aftermarket equivalent for diagnosis.