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9,253 diagnostic guides

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Find codes by symptomChoose what you notice to search matching code guides.

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 1009–1032 of 1939

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P223EO2 Sensor Reference Resistance Out Of Range Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP223E relates to o2 sensor reference resistance out of range bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P223FO2 Sensor Reference Resistance Out Of Range Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP223F relates to o2 sensor reference resistance out of range bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2240O2 Sensor Positive Current Control Circuit/Open Bank 2 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2240 relates to o2 sensor positive current control circuit/open bank 2 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2241O2 Sensor Positive Current Control Circuit Low Bank 2 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2241 relates to o2 sensor positive current control circuit low bank 2 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2242O2 Sensor Positive Current Control Circuit High Bank 2 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2242 relates to o2 sensor positive current control circuit high bank 2 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P224ANOx Sensor Heater Resistance Bank 1 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP224A relates to nox sensor heater resistance bank 1 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P224BNOx Sensor Heater Resistance Bank 1 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP224B relates to nox sensor heater resistance bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2251O2 Sensor Negative Current Control Circuit/Open Bank 1 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2251 relates to o2 sensor negative current control circuit/open bank 1 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2252O2 Sensor Negative Current Control Circuit Low Bank 1 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2252 relates to o2 sensor negative current control circuit low bank 1 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2253O2 Sensor Negative Current Control Circuit High Bank 1 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2253 relates to o2 sensor negative current control circuit high bank 1 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2254O2 Sensor Negative Current Control Circuit/Open Bank 2 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2254 relates to o2 sensor negative current control circuit/open bank 2 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2255O2 Sensor Negative Current Control Circuit Low Bank 2 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2255 relates to o2 sensor negative current control circuit low bank 2 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2256O2 Sensor Negative Current Control Circuit High Bank 2 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2256 relates to o2 sensor negative current control circuit high bank 2 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2257AIR System Control A Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2257 relates to air system control a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2258AIR System Control A Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2258 relates to air system control a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2259AIR System Control B Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2259 relates to air system control b circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P225ANOx Sensor Calibration Memory Bank 1 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP225A relates to nox sensor calibration memory bank 1 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P225BNOx Sensor Calibration Memory Bank 1 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP225B relates to nox sensor calibration memory bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P225CNOx Sensor Performance - Signal Biased/Stuck High Bank 1 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP225C relates to nox sensor performance - signal biased/stuck high bank 1 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P225DNOx Sensor Performance - Signal Biased/Stuck Low Bank 1 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP225D relates to nox sensor performance - signal biased/stuck low bank 1 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P225ENOx Sensor Performance - Signal Biased/Stuck High Bank 1 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP225E relates to nox sensor performance - signal biased/stuck high bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P225FNOx Sensor Performance - Signal Biased/Stuck Low Bank 1 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP225F relates to nox sensor performance - signal biased/stuck low bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2260AIR System Control B Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2260 relates to air system control b circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2261Turbocharger/Supercharger Bypass Valve A - MechanicalCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2261 relates to turbocharger/supercharger bypass valve a - mechanical. Check the fault conditions and vehicle-specific procedure before replacing parts.