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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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Severity

All severities9253 Low priority305 Check soon8256 Urgent621

Code family

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 4753–4776 of 9253

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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.P2243O2 Sensor Reference Voltage Circuit/Open Bank 1 Sensor 1Check soonElectrical & Charging System30–120 minutes for initial diagnosisP2243 relates to o2 sensor reference voltage circuit/open bank 1 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2244O2 Sensor Reference Voltage Performance Bank 1 Sensor 1Check soonElectrical & Charging System30–120 minutes for initial diagnosisP2244 relates to o2 sensor reference voltage performance bank 1 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2245O2 Sensor Reference Voltage Circuit Low Bank 1 Sensor 1Check soonElectrical & Charging System30–120 minutes for initial diagnosisP2245 relates to o2 sensor reference voltage circuit low bank 1 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2246O2 Sensor Reference Voltage Circuit High Bank 1 Sensor 1Check soonElectrical & Charging System30–120 minutes for initial diagnosisP2246 relates to o2 sensor reference voltage circuit high bank 1 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2247O2 Sensor Reference Voltage Circuit/Open Bank 2 Sensor 1Check soonElectrical & Charging System30–120 minutes for initial diagnosisP2247 relates to o2 sensor reference voltage circuit/open bank 2 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2248O2 Sensor Reference Voltage Performance Bank 2 Sensor 1Check soonElectrical & Charging System30–120 minutes for initial diagnosisP2248 relates to o2 sensor reference voltage performance bank 2 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2249O2 Sensor Reference Voltage Circuit Low Bank 2 Sensor 1Check soonElectrical & Charging System30–120 minutes for initial diagnosisP2249 relates to o2 sensor reference voltage circuit low 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.P224CAlternative Fuel Tank Shutoff Valve A Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP224C relates to alternative fuel tank shutoff valve a control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P224DAlternative Fuel Tank Shutoff Valve A Control Circuit Performance/Stuck OffCheck soonFuel System30–120 minutes for initial diagnosisP224D relates to alternative fuel tank shutoff valve a control circuit performance/stuck off. Check the fault conditions and vehicle-specific procedure before replacing parts.P224EAlternative Fuel Tank Shutoff Valve A Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP224E relates to alternative fuel tank shutoff valve a control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P224FAlternative Fuel Tank Shutoff Valve A Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP224F relates to alternative fuel tank shutoff valve a control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2250O2 Sensor Reference Voltage Circuit High Bank 2 Sensor 1Check soonElectrical & Charging System30–120 minutes for initial diagnosisP2250 relates to o2 sensor reference voltage circuit high bank 2 sensor 1. 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.