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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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Severity

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 1201–1224 of 8256

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P044FAIR System Switching Valve A Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP044F relates to air system switching valve a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P045AEGR B Control CircuitCheck soonEmissions System30–120 minutes for initial diagnosisP045A relates to egr b control circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P045BEGR B Control Circuit Range/PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP045B relates to egr b control circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P045CEGR B Control Circuit LowCheck soonEmissions System30–120 minutes for initial diagnosisP045C relates to egr b control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P045DEGR B Control Circuit HighCheck soonEmissions System30–120 minutes for initial diagnosisP045D relates to egr b control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P045EEGR B Control Stuck OpenCheck soonEmissions System30–120 minutes for initial diagnosisP045E relates to egr b control stuck open. Check the fault conditions and vehicle-specific procedure before replacing parts.P045FEGR B Control Stuck ClosedCheck soonEmissions System30–120 minutes for initial diagnosisP045F relates to egr b control stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P046ACatalyst Temperature Sensor 1/2 Correlation Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP046A relates to catalyst temperature sensor 1/2 correlation bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P046BCatalyst Temperature Sensor 1/2 Correlation Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP046B relates to catalyst temperature sensor 1/2 correlation bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P046CEGR Sensor A Circuit Range/PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP046C relates to egr sensor a circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P046DEGR Sensor A Circuit Intermittent/ErraticCheck soonEmissions System30–120 minutes for initial diagnosisP046D relates to egr sensor a circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P046EEGR Sensor B Circuit Range/PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP046E relates to egr sensor b circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P046FEGR Sensor B Circuit Intermittent/ErraticCheck soonEmissions System30–120 minutes for initial diagnosisP046F relates to egr sensor b circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P0470Exhaust Pressure Sensor Circuit MalfunctionCheck soonEmissions System30–120 minutes for initial diagnosisP0470 indicates a fault related to exhaust pressure sensor circuit malfunction. Learn the likely causes and a practical diagnostic order before replacing parts.P0471Exhaust Pressure Sensor Circuit Range/PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP0471 indicates a fault related to exhaust pressure sensor circuit range/performance. Learn the likely causes and a practical diagnostic order before replacing parts.P0472Exhaust Pressure Sensor Circuit Low InputCheck soonEmissions System30–120 minutes for initial diagnosisP0472 indicates a fault related to exhaust pressure sensor circuit low input. Learn the likely causes and a practical diagnostic order before replacing parts.P0473Exhaust Pressure Sensor Circuit High InputCheck soonEmissions System30–120 minutes for initial diagnosisP0473 indicates a fault related to exhaust pressure sensor circuit high input. Learn the likely causes and a practical diagnostic order before replacing parts.P0474Exhaust Pressure Sensor Circuit IntermittentCheck soonEmissions System30–120 minutes for initial diagnosisP0474 indicates a fault related to exhaust pressure sensor circuit intermittent. Learn the likely causes and a practical diagnostic order before replacing parts.P0475Exhaust Pressure Control Valve ACheck soonSensors & Electronics30–120 minutes for initial diagnosisP0475 relates to exhaust pressure control valve a. Check the fault conditions and vehicle-specific procedure before replacing parts.P0476Exhaust Pressure Control Valve A Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0476 relates to exhaust pressure control valve a range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0477Exhaust Pressure Control Valve A LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0477 relates to exhaust pressure control valve a low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0478Exhaust Pressure Control Valve A HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0478 relates to exhaust pressure control valve a high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0479Exhaust Pressure Control Valve A IntermittentCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0479 relates to exhaust pressure control valve a intermittent. Check the fault conditions and vehicle-specific procedure before replacing parts.P047AExhaust Pressure Sensor B CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP047A relates to exhaust pressure sensor b circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.