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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

Code family

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 1897–1920 of 2110

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P2D12Exhaust Flow Control Valve B Position Not LearnedCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2D12 relates to exhaust flow control valve b position not learned. Check the fault conditions and vehicle-specific procedure before replacing parts.P2D13Exhaust Flow Control Valve C Control Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2D13 relates to exhaust flow control valve c control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2D14Exhaust Flow Control Valve C Control Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2D14 relates to exhaust flow control valve c control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2D15Exhaust Flow Control Valve C Control Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2D15 relates to exhaust flow control valve c control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2D16Exhaust Flow Control Valve C Control PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2D16 relates to exhaust flow control valve c control performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2D17Exhaust Flow Control Valve C Position CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2D17 relates to exhaust flow control valve c position circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2D18Exhaust Flow Control Valve C Position Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2D18 relates to exhaust flow control valve c position circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2D19Exhaust Flow Control Valve C Position Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2D19 relates to exhaust flow control valve c position circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2D1AExhaust Flow Control Valve C Position Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2D1A relates to exhaust flow control valve c position circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2D1BExhaust Flow Control Valve C Position Not LearnedCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2D1B relates to exhaust flow control valve c position not learned. Check the fault conditions and vehicle-specific procedure before replacing parts.P2D1DReductant System Leak Detected – Small LeakCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2D1D relates to reductant system leak detected – small leak. Check the fault conditions and vehicle-specific procedure before replacing parts.P2D1EReductant System Leak Detected – Large LeakCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2D1E relates to reductant system leak detected – large leak. Check the fault conditions and vehicle-specific procedure before replacing parts.P2D1FReductant System Flow – RestrictedCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2D1F relates to reductant system flow – restricted. Check the fault conditions and vehicle-specific procedure before replacing parts.P2D20Reductant System Flow – BlockedCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2D20 relates to reductant system flow – blocked. Check the fault conditions and vehicle-specific procedure before replacing parts.P2D21Turbocharger Interstage Pressure Sensor A CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2D21 relates to turbocharger interstage pressure sensor a circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2D22Turbocharger Interstage Pressure Sensor A Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2D22 relates to turbocharger interstage pressure sensor a circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2D23Turbocharger Interstage Pressure Sensor A Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2D23 relates to turbocharger interstage pressure sensor a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2D24Turbocharger Interstage Pressure Sensor A Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2D24 relates to turbocharger interstage pressure sensor a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2D25Turbocharger Interstage Pressure Sensor A Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2D25 relates to turbocharger interstage pressure sensor a circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P2D28Cold Start Propulsion Torque PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2D28 relates to cold start propulsion torque performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2D29A/C Compressor Motor StalledCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2D29 relates to a/c compressor motor stalled. Check the fault conditions and vehicle-specific procedure before replacing parts.P2D2DCold Start Intake Manifold Runner Performance Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2D2D relates to cold start intake manifold runner performance bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2D2ECold Start Intake Manifold Runner Performance Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2D2E relates to cold start intake manifold runner performance bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2D2FCold Start Turbocharger/Supercharger A UnderboostCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2D2F relates to cold start turbocharger/supercharger a underboost. Check the fault conditions and vehicle-specific procedure before replacing parts.