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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 49–72 of 378

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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.P0486EGR Sensor B CircuitCheck soonEmissions System30–120 minutes for initial diagnosisP0486 relates to egr sensor b circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P0487EGR Throttle Control Circuit A /OpenCheck soonEmissions System30–120 minutes for initial diagnosisP0487 relates to egr throttle control circuit a /open. Check the fault conditions and vehicle-specific procedure before replacing parts.P0488EGR Throttle Control Circuit A Range/PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP0488 relates to egr throttle control circuit a range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0489EGR A Control Circuit LowCheck soonEmissions System30–120 minutes for initial diagnosisP0489 relates to egr a control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0490EGR A Control Circuit HighCheck soonEmissions System30–120 minutes for initial diagnosisP0490 relates to egr a control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P049AEGR B FlowCheck soonEmissions System30–120 minutes for initial diagnosisP049A relates to egr b flow. Check the fault conditions and vehicle-specific procedure before replacing parts.P049BEGR B Flow Insufficient DetectedCheck soonEmissions System30–120 minutes for initial diagnosisP049B relates to egr b flow insufficient detected. Check the fault conditions and vehicle-specific procedure before replacing parts.P049CEGR B Flow Excessive DetectedCheck soonEmissions System30–120 minutes for initial diagnosisP049C relates to egr b flow excessive detected. Check the fault conditions and vehicle-specific procedure before replacing parts.P049DEGR A Control Position Exceeded Learning LimitCheck soonEmissions System30–120 minutes for initial diagnosisP049D relates to egr a control position exceeded learning limit. Check the fault conditions and vehicle-specific procedure before replacing parts.P049EEGR B Control Position Exceeded Learning LimitCheck soonEmissions System30–120 minutes for initial diagnosisP049E relates to egr b control position exceeded learning limit. Check the fault conditions and vehicle-specific procedure before replacing parts.P04CEEGR Temperature Sensor C CircuitCheck soonEmissions System30–120 minutes for initial diagnosisP04CE relates to egr temperature sensor c circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P04CFEGR Temperature Sensor C Circuit Range/PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP04CF relates to egr temperature sensor c circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.