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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.

Emissions System Clear all

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Engine1049 Emissions515 Fuel1016 Sensors & Electronics2110 Transmission866 Electrical & Charging1797 Body & Restraints193 Chassis & Brakes479 Network & Communication1228

FiltersSeverity · family

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 241–264 of 515

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P23E4EGR C Control Circuit HighCheck soonEmissions System30–120 minutes for initial diagnosisP23E4 relates to egr c control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P23E5EGR C Control Stuck OpenCheck soonEmissions System30–120 minutes for initial diagnosisP23E5 relates to egr c control stuck open. Check the fault conditions and vehicle-specific procedure before replacing parts.P23E6EGR C Control Stuck ClosedCheck soonEmissions System30–120 minutes for initial diagnosisP23E6 relates to egr c control stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P23E7EGR C Flow Insufficient DetectedCheck soonEmissions System30–120 minutes for initial diagnosisP23E7 relates to egr c flow insufficient detected. Check the fault conditions and vehicle-specific procedure before replacing parts.P23E8EGR C Flow Excessive DetectedCheck soonEmissions System30–120 minutes for initial diagnosisP23E8 relates to egr c flow excessive detected. Check the fault conditions and vehicle-specific procedure before replacing parts.P2400EVAP System Leak Detection Pump Control Circuit/OpenLow priorityEmissions System30–120 minutes for initial diagnosisP2400 relates to evap system leak detection pump control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2401EVAP System Leak Detection Pump Control Circuit LowLow priorityEmissions System30–120 minutes for initial diagnosisP2401 relates to evap system leak detection pump control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2402EVAP System Leak Detection Pump Control Circuit HighLow priorityEmissions System30–120 minutes for initial diagnosisP2402 relates to evap system leak detection pump control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2403EVAP System Leak Detection Pump Sense Circuit/OpenLow priorityEmissions System30–120 minutes for initial diagnosisP2403 relates to evap system leak detection pump sense circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2404EVAP System Leak Detection Pump Sense Circuit Range/PerformanceLow priorityEmissions System30–120 minutes for initial diagnosisP2404 relates to evap system leak detection pump sense circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2405EVAP System Leak Detection Pump Sense Circuit LowLow priorityEmissions System30–120 minutes for initial diagnosisP2405 relates to evap system leak detection pump sense circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2406EVAP System Leak Detection Pump Sense Circuit HighLow priorityEmissions System30–120 minutes for initial diagnosisP2406 relates to evap system leak detection pump sense circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2407EVAP System Leak Detection Pump Sense Circuit Intermittent/ErraticLow priorityEmissions System30–120 minutes for initial diagnosisP2407 relates to evap system leak detection pump sense circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P240AEVAP System Leak Detection Pump Heater Control Circuit/OpenLow priorityEmissions System30–120 minutes for initial diagnosisP240A relates to evap system leak detection pump heater control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P240BEVAP System Leak Detection Pump Heater Control Circuit LowLow priorityEmissions System30–120 minutes for initial diagnosisP240B relates to evap system leak detection pump heater control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P240CEVAP System Leak Detection Pump Heater Control Circuit HighLow priorityEmissions System30–120 minutes for initial diagnosisP240C relates to evap system leak detection pump heater control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P240FEGR Slow ResponseCheck soonEmissions System30–120 minutes for initial diagnosisP240F relates to egr slow response. Check the fault conditions and vehicle-specific procedure before replacing parts.P2413EGR System PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP2413 relates to egr system performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2418EVAP System Switching Valve Control Circuit/OpenLow priorityEmissions System30–120 minutes for initial diagnosisP2418 relates to evap system switching valve control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2419EVAP System Switching Valve Control Circuit LowLow priorityEmissions System30–120 minutes for initial diagnosisP2419 relates to evap system switching valve control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P241FEGR Cooler B Efficiency Below ThresholdCheck soonEmissions System30–120 minutes for initial diagnosisP241F relates to egr cooler b efficiency below threshold. Check the fault conditions and vehicle-specific procedure before replacing parts.P2420EVAP System Switching Valve Control Circuit HighLow priorityEmissions System30–120 minutes for initial diagnosisP2420 relates to evap system switching valve control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2421EVAP System Vent Valve Stuck OpenLow priorityEmissions System30–120 minutes for initial diagnosisP2421 relates to evap system vent valve stuck open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2422EVAP System Vent Valve Stuck ClosedLow priorityEmissions System30–120 minutes for initial diagnosisP2422 relates to evap system vent valve stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.