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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 1249–1272 of 8256

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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.P04B0Refueling Vapor Control Valve Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP04B0 relates to refueling vapor control valve circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P04B1Refueling Vapor Control Valve Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP04B1 relates to refueling vapor control valve circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P04B2Refueling Vapor Control Valve Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP04B2 relates to refueling vapor control valve circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P04B3Refueling Vapor Control Valve Stuck Performance/Stuck OpenCheck soonFuel System30–120 minutes for initial diagnosisP04B3 relates to refueling vapor control valve stuck performance/stuck open. Check the fault conditions and vehicle-specific procedure before replacing parts.P04B4Refueling Vapor Control Valve Stuck ClosedCheck soonFuel System30–120 minutes for initial diagnosisP04B4 relates to refueling vapor control valve stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P04B5Fuel Fill Door Stuck OpenCheck soonFuel System30–120 minutes for initial diagnosisP04B5 relates to fuel fill door stuck open. Check the fault conditions and vehicle-specific procedure before replacing parts.P04B6Fuel Fill Door Stuck ClosedCheck soonFuel System30–120 minutes for initial diagnosisP04B6 relates to fuel fill door stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P04B7Fuel Fill Door Position Sensor/Switch Circuit Intermittent/ErraticCheck soonFuel System30–120 minutes for initial diagnosisP04B7 relates to fuel fill door position sensor/switch circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P04B8Fuel Fill Door Position Sensor/Switch CircuitCheck soonFuel System30–120 minutes for initial diagnosisP04B8 relates to fuel fill door position sensor/switch circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P04B9Fuel Fill Door Position Sensor/Switch Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP04B9 relates to fuel fill door position sensor/switch circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P04BAFuel Fill Door Position Sensor/Switch Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP04BA relates to fuel fill door position sensor/switch circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P04BFFuel Fill Door Unlock Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP04BF relates to fuel fill door unlock control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.