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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 817–840 of 1016

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P2A68Alternative Fuel Tank C Level Sensor Circuit Intermittent/ErraticCheck soonFuel System30–120 minutes for initial diagnosisP2A68 relates to alternative fuel tank c level sensor circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A69Alternative Fuel Rail Pressure Regulator Inlet Pressure Sensor CircuitCheck soonFuel System30–120 minutes for initial diagnosisP2A69 relates to alternative fuel rail pressure regulator inlet pressure sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A6AAlternative Fuel Rail Pressure Regulator Inlet Pressure Sensor Range/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2A6A relates to alternative fuel rail pressure regulator inlet pressure sensor range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A6BAlternative Fuel Rail Pressure Regulator Inlet Pressure Sensor Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP2A6B relates to alternative fuel rail pressure regulator inlet pressure sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A6CAlternative Fuel Rail Pressure Regulator Inlet Pressure Sensor Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2A6C relates to alternative fuel rail pressure regulator inlet pressure sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A6DAlternative Fuel Rail Pressure Regulator Inlet Pressure Sensor Circuit Intermittent/ErraticCheck soonFuel System30–120 minutes for initial diagnosisP2A6D relates to alternative fuel rail pressure regulator inlet pressure sensor circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A6EAlternative Fuel Rail Pressure Regulator Inlet Pressure Too LowCheck soonFuel System30–120 minutes for initial diagnosisP2A6E relates to alternative fuel rail pressure regulator inlet pressure too low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A6FAlternative Fuel Rail Pressure Regulator Inlet Pressure Too HighCheck soonFuel System30–120 minutes for initial diagnosisP2A6F relates to alternative fuel rail pressure regulator inlet pressure too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A70Alternative Fuel Hydraulic Fuel Pump Select Valve Control CircuitCheck soonFuel System30–120 minutes for initial diagnosisP2A70 relates to alternative fuel hydraulic fuel pump select valve control circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A71Alternative Fuel Hydraulic Fuel Pump Select Valve Control Range/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2A71 relates to alternative fuel hydraulic fuel pump select valve control range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A72Alternative Fuel Hydraulic Fuel Pump Select Valve Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP2A72 relates to alternative fuel hydraulic fuel pump select valve control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A73Alternative Fuel Hydraulic Fuel Pump Select Valve Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2A73 relates to alternative fuel hydraulic fuel pump select valve control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A74Alternative Fuel Hydraulic Fuel Pump Select Valve Control Circuit Intermittent/ErraticCheck soonFuel System30–120 minutes for initial diagnosisP2A74 relates to alternative fuel hydraulic fuel pump select valve control circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A75Alternative Fuel Hydraulic Pump Pressure Sensor CircuitCheck soonFuel System30–120 minutes for initial diagnosisP2A75 relates to alternative fuel hydraulic pump pressure sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A76Alternative Fuel Hydraulic Pump Pressure Sensor Range/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2A76 relates to alternative fuel hydraulic pump pressure sensor range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A77Alternative Fuel Hydraulic Pump Pressure Sensor Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP2A77 relates to alternative fuel hydraulic pump pressure sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.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.