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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.

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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 721–744 of 975

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P2A24Alternative Fuel Tank Shutoff Valve B Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP2A24 relates to alternative fuel tank shutoff valve b control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A25Alternative Fuel Tank Shutoff Valve B Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2A25 relates to alternative fuel tank shutoff valve b control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A26Alternative Fuel Tank Shutoff Valve C Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP2A26 relates to alternative fuel tank shutoff valve c control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A27Alternative Fuel Tank Shutoff Valve C Control Circuit Performance/Stuck OffCheck soonFuel System30–120 minutes for initial diagnosisP2A27 relates to alternative fuel tank shutoff valve c control circuit performance/stuck off. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A28Alternative Fuel Tank Shutoff Valve C Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP2A28 relates to alternative fuel tank shutoff valve c control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A29Alternative Fuel Tank Shutoff Valve C Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2A29 relates to alternative fuel tank shutoff valve c control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A2AAlternative Fuel Tank Shutoff Valve D Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP2A2A relates to alternative fuel tank shutoff valve d control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A2BAlternative Fuel Tank Shutoff Valve D Control Circuit Performance/Stuck OffCheck soonFuel System30–120 minutes for initial diagnosisP2A2B relates to alternative fuel tank shutoff valve d control circuit performance/stuck off. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A2CAlternative Fuel Tank Shutoff Valve D Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP2A2C relates to alternative fuel tank shutoff valve d control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A2DAlternative Fuel Tank Shutoff Valve D Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2A2D relates to alternative fuel tank shutoff valve d control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A2EAlternative Fuel Tank Shutoff Valve E Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP2A2E relates to alternative fuel tank shutoff valve e control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A2FAlternative Fuel Tank Shutoff Valve E Control Circuit Performance/Stuck OffCheck soonFuel System30–120 minutes for initial diagnosisP2A2F relates to alternative fuel tank shutoff valve e control circuit performance/stuck off. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A30Alternative Fuel Tank Shutoff Valve E Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP2A30 relates to alternative fuel tank shutoff valve e control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A31Alternative Fuel Tank Shutoff Valve E Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2A31 relates to alternative fuel tank shutoff valve e control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A3EAlternative Fuel Delivery ErrorCheck soonFuel System30–120 minutes for initial diagnosisP2A3E relates to alternative fuel delivery error. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A3FExcessive Time to Enter Alternative Fuel ControlCheck soonFuel System30–120 minutes for initial diagnosisP2A3F relates to excessive time to enter alternative fuel control. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A40Alternative Fuel System - Injector Leakage to Rail DetectedCheck soonFuel System30–120 minutes for initial diagnosisP2A40 relates to alternative fuel system - injector leakage to rail detected. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A41Alternative Fuel Tank B Pressure Sensor CircuitCheck soonFuel System30–120 minutes for initial diagnosisP2A41 relates to alternative fuel tank b pressure sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A42Alternative Fuel Tank B Pressure Sensor Range/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2A42 relates to alternative fuel tank b pressure sensor range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A43Alternative Fuel Tank B Pressure Sensor Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP2A43 relates to alternative fuel tank b pressure sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A44Alternative Fuel Tank B Pressure Sensor Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2A44 relates to alternative fuel tank b pressure sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A45Alternative Fuel Tank B Pressure Sensor Circuit Intermittent/ErraticCheck soonFuel System30–120 minutes for initial diagnosisP2A45 relates to alternative fuel tank b pressure sensor circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A46Alternative Fuel Tank C Pressure Sensor CircuitCheck soonFuel System30–120 minutes for initial diagnosisP2A46 relates to alternative fuel tank c pressure sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A47Alternative Fuel Tank C Pressure Sensor Range/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2A47 relates to alternative fuel tank c pressure sensor range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.