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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 73–96 of 115

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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.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.P2423HC Adsorption Catalyst Efficiency Below Threshold Bank 1Low priorityEmissions System30–120 minutes for initial diagnosisP2423 relates to hc adsorption catalyst efficiency below threshold bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2424HC Adsorption Catalyst Efficiency Below Threshold Bank 2Low priorityEmissions System30–120 minutes for initial diagnosisP2424 relates to hc adsorption catalyst efficiency below threshold bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2450EVAP System Switching Valve Performance/Stuck OpenLow priorityEmissions System30–120 minutes for initial diagnosisP2450 relates to evap system switching valve performance/stuck open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2451EVAP System Switching Valve Stuck ClosedLow priorityEmissions System30–120 minutes for initial diagnosisP2451 relates to evap system switching valve stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P24B8EVAP System Leak Detection Pump Pressure Sensor CircuitLow priorityEmissions System30–120 minutes for initial diagnosisP24B8 relates to evap system leak detection pump pressure sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P24B9EVAP System Leak Detection Pump Pressure Sensor Circuit Range/PerformanceLow priorityEmissions System30–120 minutes for initial diagnosisP24B9 relates to evap system leak detection pump pressure sensor circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P24BAEVAP System Leak Detection Pump Pressure Sensor Circuit LowLow priorityEmissions System30–120 minutes for initial diagnosisP24BA relates to evap system leak detection pump pressure sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P24BBEVAP System Leak Detection Pump Pressure Sensor Circuit HighLow priorityEmissions System30–120 minutes for initial diagnosisP24BB relates to evap system leak detection pump pressure sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P24BCEVAP System Leak Detection Pump Pressure Sensor Circuit IntermittentLow priorityEmissions System30–120 minutes for initial diagnosisP24BC relates to evap system leak detection pump pressure sensor circuit intermittent. Check the fault conditions and vehicle-specific procedure before replacing parts.P24BDEVAP System Leak Detection Pump Switching Valve Control Circuit/OpenLow priorityEmissions System30–120 minutes for initial diagnosisP24BD relates to evap system leak detection pump switching valve control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P24BEEVAP System Leak Detection Pump Switching Valve Control Circuit LowLow priorityEmissions System30–120 minutes for initial diagnosisP24BE relates to evap system leak detection pump switching valve control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P24BFEVAP System Leak Detection Pump Switching Valve Control Circuit HighLow priorityEmissions System30–120 minutes for initial diagnosisP24BF relates to evap system leak detection pump switching valve control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P24C0EVAP System Leak Detection Pump Switching Valve Stuck OnLow priorityEmissions System30–120 minutes for initial diagnosisP24C0 relates to evap system leak detection pump switching valve stuck on. Check the fault conditions and vehicle-specific procedure before replacing parts.P24C1EVAP System Leak Detection Pump Switching Valve Performance/Stuck OffLow priorityEmissions System30–120 minutes for initial diagnosisP24C1 relates to evap system leak detection pump switching valve performance/stuck off. Check the fault conditions and vehicle-specific procedure before replacing parts.P24D5EVAP System Pressure Sensor/Switch B CircuitLow priorityEmissions System30–120 minutes for initial diagnosisP24D5 relates to evap system pressure sensor/switch b circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P24D6EVAP System Pressure Sensor/Switch B Circuit Range/PerformanceLow priorityEmissions System30–120 minutes for initial diagnosisP24D6 relates to evap system pressure sensor/switch b circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P24D7EVAP System Pressure Sensor/Switch B Circuit LowLow priorityEmissions System30–120 minutes for initial diagnosisP24D7 relates to evap system pressure sensor/switch b circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P24D8EVAP System Pressure Sensor/Switch B Circuit HighLow priorityEmissions System30–120 minutes for initial diagnosisP24D8 relates to evap system pressure sensor/switch b circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P24D9EVAP System Pressure Sensor/Switch B Circuit IntermittentLow priorityEmissions System30–120 minutes for initial diagnosisP24D9 relates to evap system pressure sensor/switch b circuit intermittent. Check the fault conditions and vehicle-specific procedure before replacing parts.P2577Direct Ozone Reduction Catalyst Efficiency Below ThresholdLow priorityEmissions System30–120 minutes for initial diagnosisP2577 relates to direct ozone reduction catalyst efficiency below threshold. Check the fault conditions and vehicle-specific procedure before replacing parts.