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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 4393–4416 of 6682
P2568Direct Ozone Reduction Catalyst Temperature Sensor Circuit Range/PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP2569Direct Ozone Reduction Catalyst Temperature Sensor Circuit LowCheck soonEmissions System30–120 minutes for initial diagnosisP256AEngine Idle Speed Selector Sensor/Switch Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP256BEngine Idle Speed Selector Sensor/Switch Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP256CEngine Idle Speed Selector Sensor/Switch Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP256DEngine Idle Speed Selector Sensor/Switch Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP256EEngine Idle Speed Selector Sensor/Switch Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2570Direct Ozone Reduction Catalyst Temperature Sensor Circuit HighCheck soonEmissions System30–120 minutes for initial diagnosisP2571Direct Ozone Reduction Catalyst Temperature Sensor Circuit Intermittent/ErraticCheck soonEmissions System30–120 minutes for initial diagnosisP2572Direct Ozone Reduction Catalyst Deterioration Sensor CircuitCheck soonEmissions System30–120 minutes for initial diagnosisP2573Direct Ozone Reduction Catalyst Deterioration Sensor Circuit Range/PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP2574Direct Ozone Reduction Catalyst Deterioration Sensor Circuit LowCheck soonEmissions System30–120 minutes for initial diagnosisP2575Direct Ozone Reduction Catalyst Deterioration Sensor Circuit HighCheck soonEmissions System30–120 minutes for initial diagnosisP2576Direct Ozone Reduction Catalyst Deterioration Sensor Circuit Intermittent/ErraticCheck soonEmissions System30–120 minutes for initial diagnosisP2578Turbocharger/Supercharger Speed Sensor A CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2579Turbocharger/Supercharger Speed Sensor A Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP257AVacuum Reservoir Control Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP257BVacuum Reservoir Control Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP257CVacuum Reservoir Control Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP257DEngine Hood Switch Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP257EEngine Hood Switch Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP257FEngine Hood Switch Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2580Turbocharger/Supercharger Speed Sensor A Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2581Turbocharger/Supercharger Speed Sensor A Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosis