Catalytic Converter Protection Function (Ignition Circuit Monitoring)

In the DME M1.7 system, the cylinder reference point sensor is used for ignition circuit monitoring. See Figure . If the cylinder reference point sensor detects no ignition signal on ignition lead 6 (or 12), the supply of fuel is cut by shortening the injection signal. However, the signal is not cut completely to ensure that EML system does not revert to the emergency program. The vehicle can still be driven with the remaining row of cylinders. The cylinder reference point sensor therefore monitors the entire primary side and the cylinder 6 or 12 on the secondary side.