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9,253 diagnostic guides

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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 SystemP23E5EGR C Control Stuck OpenCheck soonEmissions SystemP23E6EGR C Control Stuck ClosedCheck soonEmissions SystemP23E7EGR C Flow Insufficient DetectedCheck soonEmissions SystemP23E8EGR C Flow Excessive DetectedCheck soonEmissions SystemP2400EVAP System Leak Detection Pump Control Circuit/OpenLow priorityEmissions SystemP2401EVAP System Leak Detection Pump Control Circuit LowLow priorityEmissions SystemP2402EVAP System Leak Detection Pump Control Circuit HighLow priorityEmissions SystemP2403EVAP System Leak Detection Pump Sense Circuit/OpenLow priorityEmissions SystemP2404EVAP System Leak Detection Pump Sense Circuit Range/PerformanceLow priorityEmissions SystemP2405EVAP System Leak Detection Pump Sense Circuit LowLow priorityEmissions SystemP2406EVAP System Leak Detection Pump Sense Circuit HighLow priorityEmissions SystemP2407EVAP System Leak Detection Pump Sense Circuit Intermittent/ErraticLow priorityEmissions SystemP240AEVAP System Leak Detection Pump Heater Control Circuit/OpenLow priorityEmissions SystemP240BEVAP System Leak Detection Pump Heater Control Circuit LowLow priorityEmissions SystemP240CEVAP System Leak Detection Pump Heater Control Circuit HighLow priorityEmissions SystemP240FEGR Slow ResponseCheck soonEmissions SystemP2413EGR System PerformanceCheck soonEmissions SystemP2418EVAP System Switching Valve Control Circuit/OpenLow priorityEmissions SystemP2419EVAP System Switching Valve Control Circuit LowLow priorityEmissions SystemP241FEGR Cooler B Efficiency Below ThresholdCheck soonEmissions SystemP2420EVAP System Switching Valve Control Circuit HighLow priorityEmissions SystemP2421EVAP System Vent Valve Stuck OpenLow priorityEmissions SystemP2422EVAP System Vent Valve Stuck ClosedLow priorityEmissions System