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Find codes by symptomChoose what you notice to search matching code guides.

Rough idle or shakingVibration while stopped Hard to startLong cranking or no-start Engine stallsCuts out at idle or on the road Hesitates or loses powerSlow response when accelerating Battery light is onCharging system warning Harsh gear changesDelayed or rough shifting

A symptom can have several causes. Treat matching codes as clues and follow the diagnostic checks in each guide.

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Engine1049 Emissions515 Fuel1016 Sensors & Electronics2110 Transmission866 Electrical & Charging1797 Body & Restraints193 Chassis & Brakes479 Network & Communication1228

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All severities9253 Low priority305 Check soon8256 Urgent621

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All families9253 P · Powertrain7353 B · Body193 C · Chassis479 U · Network1228

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These are generic OBD2 definitions. Exact make, model, engine, and year compatibility will appear after vehicle-fitment data is added.

Diagnostic codes

Showing 313–336 of 1939

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P048FExhaust Pressure Control Valve A Position Sensor/Switch Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP048F relates to exhaust pressure control valve a position sensor/switch circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P0491AIR System Insufficient Flow Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP0491 relates to air system insufficient flow bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P0492AIR System Insufficient Flow Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP0492 relates to air system insufficient flow bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P049FExhaust Pressure Control Valve BCheck soonSensors & Electronics30–120 minutes for initial diagnosisP049F relates to exhaust pressure control valve b. Check the fault conditions and vehicle-specific procedure before replacing parts.P04A0Exhaust Pressure Control Valve B Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP04A0 relates to exhaust pressure control valve b range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P04A1Exhaust Pressure Control Valve B LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP04A1 relates to exhaust pressure control valve b low. Check the fault conditions and vehicle-specific procedure before replacing parts.P04A2Exhaust Pressure Control Valve B HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP04A2 relates to exhaust pressure control valve b high. Check the fault conditions and vehicle-specific procedure before replacing parts.P04A3Exhaust Pressure Control Valve B IntermittentCheck soonSensors & Electronics30–120 minutes for initial diagnosisP04A3 relates to exhaust pressure control valve b intermittent. Check the fault conditions and vehicle-specific procedure before replacing parts.P04A4Exhaust Pressure Control Valve B Stuck OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP04A4 relates to exhaust pressure control valve b stuck open. Check the fault conditions and vehicle-specific procedure before replacing parts.P04A5Exhaust Pressure Control Valve B Stuck ClosedCheck soonSensors & Electronics30–120 minutes for initial diagnosisP04A5 relates to exhaust pressure control valve b stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P04A6Exhaust Pressure Control Valve B Position Sensor/Switch CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP04A6 relates to exhaust pressure control valve b position sensor/switch circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P04A7Exhaust Pressure Control Valve B Position Sensor/Switch Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP04A7 relates to exhaust pressure control valve b position sensor/switch circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P04A8Exhaust Pressure Control Valve B Position Sensor/Switch Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP04A8 relates to exhaust pressure control valve b position sensor/switch circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P04A9Exhaust Pressure Control Valve B Position Sensor/Switch Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP04A9 relates to exhaust pressure control valve b position sensor/switch circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P04AAExhaust Pressure Control Valve B Position Sensor/Switch Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP04AA relates to exhaust pressure control valve b position sensor/switch circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P04D3Exhaust Brake Input CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP04D3 relates to exhaust brake input circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P04D4Exhaust Brake Input Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP04D4 relates to exhaust brake input circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P04D5Exhaust Brake Input Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP04D5 relates to exhaust brake input circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P04D6Exhaust Brake Input Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP04D6 relates to exhaust brake input circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P04D7Exhaust Brake Input Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP04D7 relates to exhaust brake input circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P04DBCrankcase Ventilation System DisconnectedCheck soonSensors & Electronics30–120 minutes for initial diagnosisP04DB relates to crankcase ventilation system disconnected. Check the fault conditions and vehicle-specific procedure before replacing parts.P04E1Crankcase Ventilation Hose Connection Sensor CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP04E1 relates to crankcase ventilation hose connection sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P04E2Crankcase Ventilation Hose Connection Sensor Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP04E2 relates to crankcase ventilation hose connection sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P04E3Crankcase Ventilation Hose Connection Sensor Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP04E3 relates to crankcase ventilation hose connection sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.