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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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Diagnostic codes

Showing 3721–3744 of 7353

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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.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.