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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 1801–1824 of 2110

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P2BF5Exhaust Flow Control Valve A Position Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BF5 relates to exhaust flow control valve a position circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BF6Exhaust Flow Control Valve A Position Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BF6 relates to exhaust flow control valve a position circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BF7Exhaust Flow Control Valve A Position Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BF7 relates to exhaust flow control valve a position circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BF8Exhaust Flow Control Valve B Control Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BF8 relates to exhaust flow control valve b control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BF9Exhaust Flow Control Valve B Control Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BF9 relates to exhaust flow control valve b control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BFAExhaust Flow Control Valve B Control Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BFA relates to exhaust flow control valve b control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BFBExhaust Flow Control Valve B Control PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BFB relates to exhaust flow control valve b control performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BFCExhaust Flow Control Valve B Position CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BFC relates to exhaust flow control valve b position circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BFDExhaust Flow Control Valve B Position Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BFD relates to exhaust flow control valve b position circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BFEExhaust Flow Control Valve B Position Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BFE relates to exhaust flow control valve b position circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BFFExhaust Flow Control Valve B Position Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BFF relates to exhaust flow control valve b position circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C11Reductant Pump A Current Too LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2C11 relates to reductant pump a current too low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C21Engine Oil Temperature Sensor A/B CorrelationCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2C21 relates to engine oil temperature sensor a/b correlation. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C22Exhaust Heat Exchanger Exhaust Bypass Valve A Position Sensor CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2C22 relates to exhaust heat exchanger exhaust bypass valve a position sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C23Exhaust Heat Exchanger Exhaust Bypass Valve A Position Sensor PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2C23 relates to exhaust heat exchanger exhaust bypass valve a position sensor performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C24Exhaust Heat Exchanger Exhaust Bypass Valve A Position Sensor Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2C24 relates to exhaust heat exchanger exhaust bypass valve a position sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C25Exhaust Heat Exchanger Exhaust Bypass Valve A Position Sensor Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2C25 relates to exhaust heat exchanger exhaust bypass valve a position sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C29Turbocharger/Supercharger Bypass Valve B StuckCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2C29 relates to turbocharger/supercharger bypass valve b stuck. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C2ATurbocharger/Supercharger Bypass Valve B Position Sensor Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2C2A relates to turbocharger/supercharger bypass valve b position sensor circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C2BTurbocharger/Supercharger Bypass Valve B Position Sensor Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2C2B relates to turbocharger/supercharger bypass valve b position sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C2CTurbocharger/Supercharger Bypass Valve B Position Sensor Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2C2C relates to turbocharger/supercharger bypass valve b position sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C2DTurbocharger/Supercharger Bypass Valve B Position Exceeded Learning LimitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2C2D relates to turbocharger/supercharger bypass valve b position exceeded learning limit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C2FTurbocharger/Supercharger Bypass Valve B Driver Current/Temperature Too HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2C2F relates to turbocharger/supercharger bypass valve b driver current/temperature too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C30Ignition Coil Primary Circuit Fuse ACheck soonSensors & Electronics30–120 minutes for initial diagnosisP2C30 relates to ignition coil primary circuit fuse a. Check the fault conditions and vehicle-specific procedure before replacing parts.