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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 4105–4128 of 7353
P2244O2 Sensor Reference Voltage Performance Bank 1 Sensor 1Check soonElectrical & Charging System30–120 minutes for initial diagnosisP2245O2 Sensor Reference Voltage Circuit Low Bank 1 Sensor 1Check soonElectrical & Charging System30–120 minutes for initial diagnosisP2246O2 Sensor Reference Voltage Circuit High Bank 1 Sensor 1Check soonElectrical & Charging System30–120 minutes for initial diagnosisP2247O2 Sensor Reference Voltage Circuit/Open Bank 2 Sensor 1Check soonElectrical & Charging System30–120 minutes for initial diagnosisP2248O2 Sensor Reference Voltage Performance Bank 2 Sensor 1Check soonElectrical & Charging System30–120 minutes for initial diagnosisP2249O2 Sensor Reference Voltage Circuit Low Bank 2 Sensor 1Check soonElectrical & Charging System30–120 minutes for initial diagnosisP224ANOx Sensor Heater Resistance Bank 1 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP224BNOx Sensor Heater Resistance Bank 1 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP224CAlternative Fuel Tank Shutoff Valve A Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP224DAlternative Fuel Tank Shutoff Valve A Control Circuit Performance/Stuck OffCheck soonFuel System30–120 minutes for initial diagnosisP224EAlternative Fuel Tank Shutoff Valve A Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP224FAlternative Fuel Tank Shutoff Valve A Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2250O2 Sensor Reference Voltage Circuit High Bank 2 Sensor 1Check soonElectrical & Charging System30–120 minutes for initial diagnosisP2251O2 Sensor Negative Current Control Circuit/Open Bank 1 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2252O2 Sensor Negative Current Control Circuit Low Bank 1 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2253O2 Sensor Negative Current Control Circuit High Bank 1 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2254O2 Sensor Negative Current Control Circuit/Open Bank 2 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2255O2 Sensor Negative Current Control Circuit Low Bank 2 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2256O2 Sensor Negative Current Control Circuit High Bank 2 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2257AIR System Control A Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2258AIR System Control A Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2259AIR System Control B Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP225ANOx Sensor Calibration Memory Bank 1 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP225BNOx Sensor Calibration Memory Bank 1 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosis