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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 6505–6528 of 9253

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P2A31Alternative Fuel Tank Shutoff Valve E Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2A31 relates to alternative fuel tank shutoff valve e control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A32AFCM Power Relay Control Circuit/OpenCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP2A32 relates to afcm power relay control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A33AFCM Power Relay Control Circuit LowCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP2A33 relates to afcm power relay control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A34AFCM Power Relay Control Circuit HighCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP2A34 relates to afcm power relay control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A35AFCM Power Relay Sense CircuitCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP2A35 relates to afcm power relay sense circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A36AFCM Power Relay Sense Circuit LowCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP2A36 relates to afcm power relay sense circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A37AFCM Power Relay Sense Circuit HighCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP2A37 relates to afcm power relay sense circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A38O2 Sensor Positive Current Control Circuit/Open Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP2A38 relates to o2 sensor positive current control circuit/open bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A39O2 Sensor Positive Current Control Circuit Low Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP2A39 relates to o2 sensor positive current control circuit low bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A3AO2 Sensor Positive Current Control Circuit High Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP2A3A relates to o2 sensor positive current control circuit high bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A3BO2 Sensor Negative Current Control Circuit/Open Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP2A3B relates to o2 sensor negative current control circuit/open bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A3CO2 Sensor Negative Current Control Circuit Low Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP2A3C relates to o2 sensor negative current control circuit low bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A3DO2 Sensor Negative Current Control Circuit High Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP2A3D relates to o2 sensor negative current control circuit high bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A3EAlternative Fuel Delivery ErrorCheck soonFuel System30–120 minutes for initial diagnosisP2A3E relates to alternative fuel delivery error. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A3FExcessive Time to Enter Alternative Fuel ControlCheck soonFuel System30–120 minutes for initial diagnosisP2A3F relates to excessive time to enter alternative fuel control. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A40Alternative Fuel System - Injector Leakage to Rail DetectedCheck soonFuel System30–120 minutes for initial diagnosisP2A40 relates to alternative fuel system - injector leakage to rail detected. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A41Alternative Fuel Tank B Pressure Sensor CircuitCheck soonFuel System30–120 minutes for initial diagnosisP2A41 relates to alternative fuel tank b pressure sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A42Alternative Fuel Tank B Pressure Sensor Range/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2A42 relates to alternative fuel tank b pressure sensor range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A43Alternative Fuel Tank B Pressure Sensor Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP2A43 relates to alternative fuel tank b pressure sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A44Alternative Fuel Tank B Pressure Sensor Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2A44 relates to alternative fuel tank b pressure sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A45Alternative Fuel Tank B Pressure Sensor Circuit Intermittent/ErraticCheck soonFuel System30–120 minutes for initial diagnosisP2A45 relates to alternative fuel tank b pressure sensor circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A46Alternative Fuel Tank C Pressure Sensor CircuitCheck soonFuel System30–120 minutes for initial diagnosisP2A46 relates to alternative fuel tank c pressure sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A47Alternative Fuel Tank C Pressure Sensor Range/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2A47 relates to alternative fuel tank c pressure sensor range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2A48Alternative Fuel Tank C Pressure Sensor Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP2A48 relates to alternative fuel tank c pressure sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.