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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 793–816 of 975

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P2A78Alternative Fuel Hydraulic Pump Pressure Sensor Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2A78 relates to alternative fuel hydraulic pump pressure sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A79Alternative Fuel Hydraulic Pump Pressure Sensor Circuit Intermittent/ErraticCheck soonFuel System30–120 minutes for initial diagnosisP2A79 relates to alternative fuel hydraulic pump pressure sensor circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A7AAlternative Fuel Hydraulic Pressure Sensor CircuitCheck soonFuel System30–120 minutes for initial diagnosisP2A7A relates to alternative fuel hydraulic pressure sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A7BAlternative Fuel Hydraulic Pressure Sensor Range/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2A7B relates to alternative fuel hydraulic pressure sensor range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A7CAlternative Fuel Hydraulic Pressure Sensor Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP2A7C relates to alternative fuel hydraulic pressure sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A7DAlternative Fuel Hydraulic Pressure Sensor Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2A7D relates to alternative fuel hydraulic pressure sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A7EAlternative Fuel Hydraulic Pressure Sensor Circuit Intermitttent/ErraticCheck soonFuel System30–120 minutes for initial diagnosisP2A7E relates to alternative fuel hydraulic pressure sensor circuit intermitttent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A7FAlternative Fuel Pump A Compression Stroke Valve Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP2A7F relates to alternative fuel pump a compression stroke valve control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A80Alternative Fuel Pump A Compression Stroke Valve Control Circuit Range/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2A80 relates to alternative fuel pump a compression stroke valve control circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A81Alternative Fuel Pump A Compression Stroke Valve Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP2A81 relates to alternative fuel pump a compression stroke valve control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A82Alternative Fuel Pump A Compression Stroke Valve Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2A82 relates to alternative fuel pump a compression stroke valve control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A83Alternative Fuel Pump B Compression Stroke Valve Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP2A83 relates to alternative fuel pump b compression stroke valve control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A84Alternative Fuel Pump B Compression Stroke Valve Control Circuit Range/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2A84 relates to alternative fuel pump b compression stroke valve control circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A85Alternative Fuel Pump B Compression Stroke Valve Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP2A85 relates to alternative fuel pump b compression stroke valve control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A86Alternative Fuel Pump B Compression Stroke Valve Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2A86 relates to alternative fuel pump b compression stroke valve control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A87Alternative Fuel Pump C Compression Stroke Valve Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP2A87 relates to alternative fuel pump c compression stroke valve control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A88Alternative Fuel Pump C Compression Stroke Valve Control Circuit Range/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2A88 relates to alternative fuel pump c compression stroke valve control circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A89Alternative Fuel Pump C Compression Stroke Valve Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP2A89 relates to alternative fuel pump c compression stroke valve control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A8AAlternative Fuel Pump C Compression Stroke Valve Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2A8A relates to alternative fuel pump c compression stroke valve control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A8BAlternative Fuel Vaporizer A PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2A8B relates to alternative fuel vaporizer a performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A8CAlternative Fuel Vaporizer B PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2A8C relates to alternative fuel vaporizer b performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A8DAlternative Fuel Vaporizer C PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2A8D relates to alternative fuel vaporizer c performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A8EAlternative Fuel Pump A PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2A8E relates to alternative fuel pump a performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A8FAlternative Fuel Pump B PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2A8F relates to alternative fuel pump b performance. Check the fault conditions and vehicle-specific procedure before replacing parts.