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9,253 diagnostic guides
Find codes by symptomChoose what you notice to search matching code guides.
Rough idle or shakingVibration while stoppedHard to startLong cranking or no-startEngine stallsCuts out at idle or on the roadHesitates or loses powerSlow response when acceleratingBattery light is onCharging system warningHarsh 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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These are generic OBD2 definitions. Exact make, model, engine, and year compatibility will appear after vehicle-fitment data is added.
Diagnostic codes
Showing 217–240 of 305
P24C1EVAP System Leak Detection Pump Switching Valve Performance/Stuck OffLow priorityEmissions System30–120 minutes for initial diagnosisP24D5EVAP System Pressure Sensor/Switch B CircuitLow priorityEmissions System30–120 minutes for initial diagnosisP24D6EVAP System Pressure Sensor/Switch B Circuit Range/PerformanceLow priorityEmissions System30–120 minutes for initial diagnosisP24D7EVAP System Pressure Sensor/Switch B Circuit LowLow priorityEmissions System30–120 minutes for initial diagnosisP24D8EVAP System Pressure Sensor/Switch B Circuit HighLow priorityEmissions System30–120 minutes for initial diagnosisP24D9EVAP System Pressure Sensor/Switch B Circuit IntermittentLow priorityEmissions System30–120 minutes for initial diagnosisP2515A/C Refrigerant Pressure Sensor B CircuitLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2516A/C Refrigerant Pressure Sensor B Circuit Range/PerformanceLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2517A/C Refrigerant Pressure Sensor B Circuit LowLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2518A/C Refrigerant Pressure Sensor B Circuit HighLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2519A/C Request A CircuitLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2520A/C Request A Circuit LowLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2521A/C Request A Circuit HighLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2522A/C Request B CircuitLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2523A/C Request B Circuit LowLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2524A/C Request B Circuit HighLow prioritySensors & Electronics30–120 minutes for initial diagnosisP255FA/C Request A Circuit Range/PerformanceLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2561A/C Control Module Requested MIL IlluminationLow prioritySensors & Electronics30–120 minutes for initial diagnosisP256FA/C Request B Circuit Range/PerformanceLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2577Direct Ozone Reduction Catalyst Efficiency Below ThresholdLow priorityEmissions System30–120 minutes for initial diagnosisP2583Cruise Control Front Distance Range Sensor Single Sensor or CenterLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2591Cruise Control Front Distance Range Sensor LeftLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2592Cruise Control Front Distance Range Sensor RightLow prioritySensors & Electronics30–120 minutes for initial diagnosisP25B0Fuel Level Sensor A StuckLow priorityFuel System30–120 minutes for initial diagnosis