Introduction to On Board Diagnostics (II)

Fundamentals of PowertrainControl strategies & OBD IIDiagnosticsEGR Sensor /Valve ( DTCs 400-408):408):EGR sensor/ valve diagnostics areperformed for deterioration of exhaust gas flow characteristics. s. In caseof EGR flow malfunction fault code 400 is assigned. If the EGR R flow isindicating insufficient flow, fault code 401 is assigned. If the e EGR flowis indicating excessive flow, fault code 402 is assigned. If the EGRcircuit malfunction, fault code 403 is assigned. If the EGR circuit isindicating range/performance problem , fault code 404 is assigned.If the EGR sensor A circuit is indicating low value, fault code c405 isassigned. If the EGR sensor A circuit is indicating high value, fault code406 is assigned. Similar faults on sensor “B” circuit are assigned faultcodes 407, 408 respectively. EGR sensor/valve diagnostics aredescribed in detail in later section.