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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 1297–1320 of 1939

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P2529Vacuum Reservoir Pressure Sensor Circuit IntermittentCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2529 relates to vacuum reservoir pressure sensor circuit intermittent. Check the fault conditions and vehicle-specific procedure before replacing parts.P252AEngine Oil Quality Sensor CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP252A relates to engine oil quality sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P252BEngine Oil Quality Sensor Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP252B relates to engine oil quality sensor circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.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.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.P2544Torque Management Request Input Signal ACheck soonSensors & Electronics30–120 minutes for initial diagnosisP2544 relates to torque management request input signal a. Check the fault conditions and vehicle-specific procedure before replacing parts.P2545Torque Management Request Input Signal A Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2545 relates to torque management request input signal a range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.