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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.

Fuel System Check soon Clear all

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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 625–648 of 975

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P23FCCylinder 11 Injector B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23FC relates to cylinder 11 injector b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23FDCylinder 12 Injector B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23FD relates to cylinder 12 injector b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23FEBank 1 System B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23FE relates to bank 1 system b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23FFBank 2 System B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23FF relates to bank 2 system b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P240DAlternative Fuel Low Pressure System LeakCheck soonFuel System30–120 minutes for initial diagnosisP240D relates to alternative fuel low pressure system leak. Check the fault conditions and vehicle-specific procedure before replacing parts.P240EAlternative Fuel High Pressure System LeakCheck soonFuel System30–120 minutes for initial diagnosisP240E relates to alternative fuel high pressure system leak. Check the fault conditions and vehicle-specific procedure before replacing parts.P249CExcessive Time To Enter Closed Loop Reductant Injection ControlCheck soonFuel System30–120 minutes for initial diagnosisP249C relates to excessive time to enter closed loop reductant injection control. Check the fault conditions and vehicle-specific procedure before replacing parts.P249DClosed Loop Reductant Injection Control At Limit - Flow Too LowCheck soonFuel System30–120 minutes for initial diagnosisP249D relates to closed loop reductant injection control at limit - flow too low. Check the fault conditions and vehicle-specific procedure before replacing parts.P249EClosed Loop Reductant Injection Control At Limit - Flow Too HighCheck soonFuel System30–120 minutes for initial diagnosisP249E relates to closed loop reductant injection control at limit - flow too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P24F3Reductant Tank Temperature/Fuel Temperature CorrelationCheck soonFuel System30–120 minutes for initial diagnosisP24F3 relates to reductant tank temperature/fuel temperature correlation. Check the fault conditions and vehicle-specific procedure before replacing parts.P2539Low Pressure Fuel System Sensor CircuitCheck soonFuel System30–120 minutes for initial diagnosisP2539 relates to low pressure fuel system sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2540Low Pressure Fuel System Sensor Circuit Range/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2540 relates to low pressure fuel system sensor circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2541Low Pressure Fuel System Sensor Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP2541 relates to low pressure fuel system sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2542Low Pressure Fuel System Sensor Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2542 relates to low pressure fuel system sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2543Low Pressure Fuel System Sensor Circuit IntermittentCheck soonFuel System30–120 minutes for initial diagnosisP2543 relates to low pressure fuel system sensor circuit intermittent. Check the fault conditions and vehicle-specific procedure before replacing parts.P2552Throttle/Fuel Inhibit A CircuitCheck soonFuel System30–120 minutes for initial diagnosisP2552 relates to throttle/fuel inhibit a circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2553Throttle/Fuel Inhibit A Circuit Range/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2553 relates to throttle/fuel inhibit a circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2554Throttle/Fuel Inhibit A Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP2554 relates to throttle/fuel inhibit a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2555Throttle/Fuel Inhibit A Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2555 relates to throttle/fuel inhibit a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2584Fuel Additive Control Module Requested MIL IlluminationCheck soonFuel System30–120 minutes for initial diagnosisP2584 relates to fuel additive control module requested mil illumination. Check the fault conditions and vehicle-specific procedure before replacing parts.P2585Fuel Additive Control Module Warning Lamp RequestCheck soonFuel System30–120 minutes for initial diagnosisP2585 relates to fuel additive control module warning lamp request. Check the fault conditions and vehicle-specific procedure before replacing parts.P25A4Fuel Mode Select Switch CircuitCheck soonFuel System30–120 minutes for initial diagnosisP25A4 relates to fuel mode select switch circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P25A5Fuel Mode Select Switch PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP25A5 relates to fuel mode select switch performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P25A6Fuel Mode Select Switch Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP25A6 relates to fuel mode select switch circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.