What does obd code 409 mean?

OBD code P0409 indicates an issue with the Exhaust Gas Recirculation (EGR) sensor. Specifically, it signifies that the sensor's signal is out of range or not functioning properly, which can lead to increased emissions and reduced engine performance. Common causes include a faulty EGR sensor, wiring issues, or problems with the EGR valve itself. Addressing this code typically involves inspecting and, if necessary, replacing the faulty components.