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9,253 diagnostic guides

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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 721–744 of 987

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P2C3ACylinder Head Temperature Sensor B Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP2C3A relates to cylinder head temperature sensor b circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C3BCylinder Head Temperature Sensor B Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP2C3B relates to cylinder head temperature sensor b circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C3CCylinder Head Temperature Sensor B Circuit Intermittent/ErraticCheck soonEngine Problems30–120 minutes for initial diagnosisP2C3C relates to cylinder head temperature sensor b circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C3DCylinder Head Temperature Sensor A/B CorrelationCheck soonEngine Problems30–120 minutes for initial diagnosisP2C3D relates to cylinder head temperature sensor a/b correlation. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C3EFan 4 Control CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP2C3E relates to fan 4 control circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C3FFan 4 Control Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP2C3F relates to fan 4 control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C40Fan 4 Control Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP2C40 relates to fan 4 control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C41Fan 3 Performance/Stuck OffCheck soonEngine Problems30–120 minutes for initial diagnosisP2C41 relates to fan 3 performance/stuck off. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C42Fan 4 Performance/Stuck OffCheck soonEngine Problems30–120 minutes for initial diagnosisP2C42 relates to fan 4 performance/stuck off. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C48Coolant Pump C Control Circuit Performance/Stuck OffCheck soonEngine Problems30–120 minutes for initial diagnosisP2C48 relates to coolant pump c control circuit performance/stuck off. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C49Coolant Pump D Control Circuit Performance/Stuck OffCheck soonEngine Problems30–120 minutes for initial diagnosisP2C49 relates to coolant pump d control circuit performance/stuck off. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C66Hybrid/EV Electronics Coolant Pump A UnderspeedCheck soonEngine Problems30–120 minutes for initial diagnosisP2C66 relates to hybrid/ev electronics coolant pump a underspeed. Check the fault conditions and vehicle-specific procedure before replacing parts.P2C68Hybrid/EV Electronics Coolant Pump A Stuck/StalledCheck soonEngine Problems30–120 minutes for initial diagnosisP2C68 relates to hybrid/ev electronics coolant pump a stuck/stalled. Check the fault conditions and vehicle-specific procedure before replacing parts.P2CA1Charge Air Cooler Coolant Pump Sense Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP2CA1 relates to charge air cooler coolant pump sense circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2CA2Charge Air Cooler Coolant Pump Sense Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP2CA2 relates to charge air cooler coolant pump sense circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2CA3Charge Air Cooler Coolant Pump Sense Circuit PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP2CA3 relates to charge air cooler coolant pump sense circuit performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2CADCharge Air Cooler Coolant Pump B Control Circuit/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP2CAD relates to charge air cooler coolant pump b control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2CAECharge Air Cooler Coolant Pump B Control Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP2CAE relates to charge air cooler coolant pump b control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2CAFCharge Air Cooler Coolant Pump B Control Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP2CAF relates to charge air cooler coolant pump b control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2CB0Charge Air Cooler Coolant Pump B PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP2CB0 relates to charge air cooler coolant pump b performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2CB2Charge Air Cooler Coolant Pump B UnderspeedCheck soonEngine Problems30–120 minutes for initial diagnosisP2CB2 relates to charge air cooler coolant pump b underspeed. Check the fault conditions and vehicle-specific procedure before replacing parts.P2CB3Charge Air Cooler Coolant Pump B Stuck/StalledCheck soonEngine Problems30–120 minutes for initial diagnosisP2CB3 relates to charge air cooler coolant pump b stuck/stalled. Check the fault conditions and vehicle-specific procedure before replacing parts.P2CB5Charge Air Cooler Coolant Pump B Control Module OvertemperatureCheck soonEngine Problems30–120 minutes for initial diagnosisP2CB5 relates to charge air cooler coolant pump b control module overtemperature. Check the fault conditions and vehicle-specific procedure before replacing parts.P2CB9Fan 2 UnderspeedCheck soonEngine Problems30–120 minutes for initial diagnosisP2CB9 relates to fan 2 underspeed. Check the fault conditions and vehicle-specific procedure before replacing parts.