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9,253 diagnostic guides

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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 601–624 of 975

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P23D3Cylinder 1 Fuel Heater Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP23D3 relates to cylinder 1 fuel heater control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P23D4Cylinder 1 Fuel Heater PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP23D4 relates to cylinder 1 fuel heater performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23D5Cylinder 2 Fuel Heater Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP23D5 relates to cylinder 2 fuel heater control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P23D6Cylinder 2 Fuel Heater Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP23D6 relates to cylinder 2 fuel heater control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P23D7Cylinder 2 Fuel Heater Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP23D7 relates to cylinder 2 fuel heater control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P23D8Cylinder 2 Fuel Heater PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP23D8 relates to cylinder 2 fuel heater performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23D9Cylinder 3 Fuel Heater Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP23D9 relates to cylinder 3 fuel heater control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P23DACylinder 3 Fuel Heater Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP23DA relates to cylinder 3 fuel heater control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P23DBCylinder 3 Fuel Heater Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP23DB relates to cylinder 3 fuel heater control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P23DCCylinder 3 Fuel Heater PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP23DC relates to cylinder 3 fuel heater performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23DDCylinder 4 Fuel Heater Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP23DD relates to cylinder 4 fuel heater control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P23DECylinder 4 Fuel Heater Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP23DE relates to cylinder 4 fuel heater control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P23DFCylinder 4 Fuel Heater Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP23DF relates to cylinder 4 fuel heater control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P23E0Cylinder 4 Fuel Heater PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP23E0 relates to cylinder 4 fuel heater performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23F2Cylinder 1 Injector B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23F2 relates to cylinder 1 injector b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23F3Cylinder 2 Injector B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23F3 relates to cylinder 2 injector b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23F4Cylinder 3 Injector B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23F4 relates to cylinder 3 injector b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23F5Cylinder 4 Injector B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23F5 relates to cylinder 4 injector b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23F6Cylinder 5 Injector B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23F6 relates to cylinder 5 injector b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23F7Cylinder 6 Injector B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23F7 relates to cylinder 6 injector b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23F8Cylinder 7 Injector B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23F8 relates to cylinder 7 injector b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23F9Cylinder 8 Injector B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23F9 relates to cylinder 8 injector b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23FACylinder 9 Injector B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23FA relates to cylinder 9 injector b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23FBCylinder 10 Injector B Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP23FB relates to cylinder 10 injector b air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.