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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 169–192 of 305
P0EE5A/C Refrigerant Distribution Valve B Control Circuit HighLow priorityElectrical & Charging System45–120 minutes for initial diagnosisP2024EVAP Fuel Vapor Temperature Sensor CircuitLow priorityEmissions System30–120 minutes for initial diagnosisP2025EVAP Fuel Vapor Temperature Sensor PerformanceLow priorityEmissions System30–120 minutes for initial diagnosisP2026EVAP Fuel Vapor Temperature Sensor Circuit Low VoltageLow priorityEmissions System30–120 minutes for initial diagnosisP2028EVAP Fuel Vapor Temperature Sensor Circuit IntermittentLow priorityEmissions System30–120 minutes for initial diagnosisP2065Fuel Level Sensor B CircuitLow priorityFuel System30–120 minutes for initial diagnosisP2066Fuel Level Sensor B PerformanceLow priorityFuel System30–120 minutes for initial diagnosisP2067Fuel Level Sensor B Circuit LowLow priorityFuel System30–120 minutes for initial diagnosisP2068Fuel Level Sensor B Circuit HighLow priorityFuel System30–120 minutes for initial diagnosisP2069Fuel Level Sensor B Circuit IntermittentLow priorityFuel System30–120 minutes for initial diagnosisP20EESCR NOx Catalyst Efficiency Below Threshold Bank 1 Catalyst 1Low priorityEmissions System30–120 minutes for initial diagnosisP20EFSCR NOx Pre- Catalyst Efficiency Below Threshold Bank 1Low priorityEmissions System30–120 minutes for initial diagnosisP20F2SCR NOx Catalyst Efficiency Below Threshold Bank 2Low priorityEmissions System30–120 minutes for initial diagnosisP20F3SCR NOx Pre- Catalyst Efficiency Below Threshold Bank 2Low priorityEmissions System30–120 minutes for initial diagnosisP2400EVAP System Leak Detection Pump Control Circuit/OpenLow priorityEmissions System30–120 minutes for initial diagnosisP2401EVAP System Leak Detection Pump Control Circuit LowLow priorityEmissions System30–120 minutes for initial diagnosisP2402EVAP System Leak Detection Pump Control Circuit HighLow priorityEmissions System30–120 minutes for initial diagnosisP2403EVAP System Leak Detection Pump Sense Circuit/OpenLow priorityEmissions System30–120 minutes for initial diagnosisP2404EVAP System Leak Detection Pump Sense Circuit Range/PerformanceLow priorityEmissions System30–120 minutes for initial diagnosisP2405EVAP System Leak Detection Pump Sense Circuit LowLow priorityEmissions System30–120 minutes for initial diagnosisP2406EVAP System Leak Detection Pump Sense Circuit HighLow priorityEmissions System30–120 minutes for initial diagnosisP2407EVAP System Leak Detection Pump Sense Circuit Intermittent/ErraticLow priorityEmissions System30–120 minutes for initial diagnosisP2408Fuel Cap Sensor/Switch CircuitLow priorityFuel System30–120 minutes for initial diagnosisP2409Fuel Cap Sensor/Switch Circuit Range/PerformanceLow priorityFuel System30–120 minutes for initial diagnosis