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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

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 4849–4872 of 7353

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P252CEngine Oil Quality Sensor Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP252C relates to engine oil quality sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P252DEngine Oil Quality Sensor Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP252D relates to engine oil quality sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P252EEngine Oil Quality Sensor Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP252E relates to engine oil quality sensor circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P252FEngine Oil Level Too HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP252F relates to engine oil level too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2530Ignition Switch Run Position CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2530 relates to ignition switch run position circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2531Ignition Switch Run Position Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2531 relates to ignition switch run position circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2532Ignition Switch Run Position Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2532 relates to ignition switch run position circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2533Ignition Switch On/Start Position CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2533 relates to ignition switch on/start position circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2534Ignition Switch On/Start Position Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2534 relates to ignition switch on/start position circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2535Ignition Switch On/Start Position Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2535 relates to ignition switch on/start position circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2536Ignition Switch Accessory Position CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2536 relates to ignition switch accessory position circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2537Ignition Switch Accessory Position Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2537 relates to ignition switch accessory position circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2538Ignition Switch Accessory Position Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2538 relates to ignition switch accessory position circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2539Low Pressure Fuel System Sensor CircuitCheck soonFuel System30–120 minutes for initial diagnosisP2539 relates to low pressure fuel system sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P253APTO Sense Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP253A relates to pto sense circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P253BPTO Sense Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP253B relates to pto sense circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P253CPTO Sense Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP253C relates to pto sense circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P253DPTO Sense Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP253D relates to pto sense circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P253EPTO Sense Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP253E relates to pto sense circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P253FEngine Oil DeterioratedCheck soonSensors & Electronics30–120 minutes for initial diagnosisP253F relates to engine oil deteriorated. Check the fault conditions and vehicle-specific procedure before replacing parts.P2540Low Pressure Fuel System Sensor Circuit Range/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2540 relates to low pressure fuel system sensor circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2541Low Pressure Fuel System Sensor Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP2541 relates to low pressure fuel system sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2542Low Pressure Fuel System Sensor Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2542 relates to low pressure fuel system sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2543Low Pressure Fuel System Sensor Circuit IntermittentCheck soonFuel System30–120 minutes for initial diagnosisP2543 relates to low pressure fuel system sensor circuit intermittent. Check the fault conditions and vehicle-specific procedure before replacing parts.