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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 1273–1296 of 1939

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P2505ECM/PCM Power Input SignalCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2505 relates to ecm/pcm power input signal. Check the fault conditions and vehicle-specific procedure before replacing parts.P2506ECM/PCM Power Input Signal Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2506 relates to ecm/pcm power input signal range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2507ECM/PCM Power Input Signal LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2507 relates to ecm/pcm power input signal low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2508ECM/PCM Power Input Signal HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2508 relates to ecm/pcm power input signal high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2509ECM/PCM Power Input Signal IntermittentCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2509 relates to ecm/pcm power input signal intermittent. Check the fault conditions and vehicle-specific procedure before replacing parts.P250AEngine Oil Level Sensor CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP250A relates to engine oil level sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P250BEngine Oil Level Sensor Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP250B relates to engine oil level sensor circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P250CEngine Oil Level Sensor Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP250C relates to engine oil level sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P250DEngine Oil Level Sensor Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP250D relates to engine oil level sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P250EEngine Oil Level Sensor Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP250E relates to engine oil level sensor circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P250FEngine Oil Level Too LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP250F relates to engine oil level too low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2512Event Data Recorder Request Circuit/ OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2512 relates to event data recorder request circuit/ open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2513Event Data Recorder Request Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2513 relates to event data recorder request circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2514Event Data Recorder Request Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2514 relates to event data recorder request circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P251APTO Enable Switch Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP251A relates to pto enable switch circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P251BPTO Enable Switch Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP251B relates to pto enable switch circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P251CPTO Enable Switch Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP251C relates to pto enable switch circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P251DPTO Engine Shutdown Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP251D relates to pto engine shutdown circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P251EPTO Engine Shutdown Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP251E relates to pto engine shutdown circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P251FPTO Engine Shutdown Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP251F relates to pto engine shutdown circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2525Vacuum Reservoir Pressure Sensor CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2525 relates to vacuum reservoir pressure sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2526Vacuum Reservoir Pressure Sensor Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2526 relates to vacuum reservoir pressure sensor circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2527Vacuum Reservoir Pressure Sensor Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2527 relates to vacuum reservoir pressure sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2528Vacuum Reservoir Pressure Sensor Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2528 relates to vacuum reservoir pressure sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.