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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 385–408 of 1016

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P20CBExhaust Aftertreatment Fuel Injector A Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP20CB relates to exhaust aftertreatment fuel injector a control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P20CCExhaust Aftertreatment Fuel Injector A Control PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP20CC relates to exhaust aftertreatment fuel injector a control performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P20CDExhaust Aftertreatment Fuel Injector A Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP20CD relates to exhaust aftertreatment fuel injector a control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P20CEExhaust Aftertreatment Fuel Injector A Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP20CE relates to exhaust aftertreatment fuel injector a control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P20CFExhaust Aftertreatment Fuel Injector A Stuck OpenCheck soonFuel System30–120 minutes for initial diagnosisP20CF relates to exhaust aftertreatment fuel injector a stuck open. Check the fault conditions and vehicle-specific procedure before replacing parts.P20D0Exhaust Aftertreatment Fuel Injector A Stuck ClosedCheck soonFuel System30–120 minutes for initial diagnosisP20D0 relates to exhaust aftertreatment fuel injector a stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P20D1Exhaust Aftertreatment Fuel Injector B Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP20D1 relates to exhaust aftertreatment fuel injector b control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P20D2Exhaust Aftertreatment Fuel Injector B Control PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP20D2 relates to exhaust aftertreatment fuel injector b control performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P20D3Exhaust Aftertreatment Fuel Injector B Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP20D3 relates to exhaust aftertreatment fuel injector b control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P20D4Exhaust Aftertreatment Fuel Injector B Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP20D4 relates to exhaust aftertreatment fuel injector b control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P20D5Exhaust Aftertreatment Fuel Injector B Stuck OpenCheck soonFuel System30–120 minutes for initial diagnosisP20D5 relates to exhaust aftertreatment fuel injector b stuck open. Check the fault conditions and vehicle-specific procedure before replacing parts.P20D6Exhaust Aftertreatment Fuel Injector B Stuck ClosedCheck soonFuel System30–120 minutes for initial diagnosisP20D6 relates to exhaust aftertreatment fuel injector b stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P20D7Exhaust Aftertreatment Fuel Supply Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP20D7 relates to exhaust aftertreatment fuel supply control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P20D8Exhaust Aftertreatment Fuel Supply Control PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP20D8 relates to exhaust aftertreatment fuel supply control performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P20D9Exhaust Aftertreatment Fuel Supply Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP20D9 relates to exhaust aftertreatment fuel supply control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P20DAExhaust Aftertreatment Fuel Supply Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP20DA relates to exhaust aftertreatment fuel supply control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P20DBExhaust Aftertreatment Fuel Supply Control Stuck OpenCheck soonFuel System30–120 minutes for initial diagnosisP20DB relates to exhaust aftertreatment fuel supply control stuck open. Check the fault conditions and vehicle-specific procedure before replacing parts.P20DCExhaust Aftertreatment Fuel Supply Control Stuck ClosedCheck soonFuel System30–120 minutes for initial diagnosisP20DC relates to exhaust aftertreatment fuel supply control stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P20DDExhaust Aftertreatment Fuel Pressure Sensor CircuitCheck soonFuel System30–120 minutes for initial diagnosisP20DD relates to exhaust aftertreatment fuel pressure sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P20DEExhaust Aftertreatment Fuel Pressure Sensor Circuit Range/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP20DE relates to exhaust aftertreatment fuel pressure sensor circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P20DFExhaust Aftertreatment Fuel Pressure Sensor Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP20DF relates to exhaust aftertreatment fuel pressure sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P20E0Exhaust Aftertreatment Fuel Pressure Sensor Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP20E0 relates to exhaust aftertreatment fuel pressure sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P20E1Exhaust Aftertreatment Fuel Pressure Sensor Circuit Intermittent/ErraticCheck soonFuel System30–120 minutes for initial diagnosisP20E1 relates to exhaust aftertreatment fuel pressure sensor circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P20E6Reductant Injection Air Pressure Too LowCheck soonFuel System30–120 minutes for initial diagnosisP20E6 relates to reductant injection air pressure too low. Check the fault conditions and vehicle-specific procedure before replacing parts.