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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 841–864 of 1016

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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.P2A90Alternative Fuel Pump C PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2A90 relates to alternative fuel pump c performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A91Alternative Fuel Tank Select Valve A Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP2A91 relates to alternative fuel tank select valve a control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A92Alternative Fuel Tank Select Valve A Control PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2A92 relates to alternative fuel tank select valve a control performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A93Alternative Fuel Tank Select Valve A Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP2A93 relates to alternative fuel tank select valve a control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A94Alternative Fuel Tank Select Valve A Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2A94 relates to alternative fuel tank select valve a control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A95Alternative Fuel Tank Select Valve B Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP2A95 relates to alternative fuel tank select valve b control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A96Alternative Fuel Tank Select Valve B Control Circuit PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2A96 relates to alternative fuel tank select valve b control circuit performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A97Alternative Fuel Tank Select Valve B Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP2A97 relates to alternative fuel tank select valve b control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.