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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 3601–3624 of 8256

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P20BDReductant Heater B Control Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP20BD relates to reductant heater b control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P20BEReductant Heater B Control Circuit PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP20BE relates to reductant heater b control circuit performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P20BFReductant Heater B Control Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP20BF relates to reductant heater b control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P20C0Reductant Heater B Control Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP20C0 relates to reductant heater b control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P20C1Reductant Heater C Control Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP20C1 relates to reductant heater c control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P20C2Reductant Heater C Control Circuit PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP20C2 relates to reductant heater c control circuit performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P20C3Reductant Heater C Control Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP20C3 relates to reductant heater c control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P20C4Reductant Heater C Control Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP20C4 relates to reductant heater c control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P20C5Reductant Heater D Control Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP20C5 relates to reductant heater d control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P20C6Reductant Heater D Control Circuit PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP20C6 relates to reductant heater d control circuit performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P20C7Reductant Heater D Control Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP20C7 relates to reductant heater d control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P20C8Reductant Heater D Control Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP20C8 relates to reductant heater d control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P20C9Reductant Control Module Requested MIL IlluminationCheck soonSensors & Electronics30–120 minutes for initial diagnosisP20C9 relates to reductant control module requested mil illumination. Check the fault conditions and vehicle-specific procedure before replacing parts.P20CAReductant Injection Air Pressure LeakageCheck soonFuel System30–120 minutes for initial diagnosisP20CA relates to reductant injection air pressure leakage. Check the fault conditions and vehicle-specific procedure before replacing parts.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.