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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

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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 313–336 of 621

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P0298Engine Oil Over TemperatureUrgentSensors & Electronics30–120 minutes for initial diagnosisP0298 relates to engine oil over temperature. Check the fault conditions and vehicle-specific procedure before replacing parts.P0300Random/Multiple Cylinder Misfire DetectedUrgentEngine Problems30–90 minutesDiagnose P0300 random misfire code. Learn why multiple cylinders are misfiring and the systematic approach to finding the cause.P0301Cylinder 1 Misfire Detected - Diagnosis GuideUrgentEngine Problems30–75 minutesComplete guide to P0301 cylinder 1 misfire. Find out what's causing the misfire and how to fix it step by step.P0302Cylinder 2 Misfire Detected - Causes & FixesUrgentEngine Problems30–75 minutesComplete guide to P0302 cylinder 2 misfire. Diagnose and fix the misfire with our step-by-step troubleshooting guide.P0303Cylinder 3 Misfire Detected - Diagnosis GuideUrgentEngine Problems30–75 minutesFix P0303 cylinder 3 misfire code. Learn the common causes and proven solutions for cylinder 3 misfiring.P0307Cylinder 7 Misfire DetectedUrgentEngine Problems1–3 hours for initial diagnosisP0307 means Cylinder 7 Misfire Detected. Learn the likely symptoms, common causes, and a safe diagnostic order before replacing parts.P0308Cylinder 8 Misfire DetectedUrgentEngine Problems1–3 hours for initial diagnosisP0308 means Cylinder 8 Misfire Detected. Learn the likely symptoms, common causes, and a safe diagnostic order before replacing parts.P0316Misfire Detected on Startup First 1000 RevolutionsUrgentEngine Problems1–3 hours for initial diagnosisP0316 means Misfire Detected on Startup First 1000 Revolutions. Learn the likely symptoms, common causes, and a safe diagnostic order before replacing parts.P0480Cooling Fan 1 Control Circuit MalfunctionUrgentEngine Problems30–120 minutes for initial diagnosisP0480 indicates a fault related to cooling fan 1 control circuit malfunction. Learn the likely causes and a practical diagnostic order before replacing parts.P0481Cooling Fan 2 Control Circuit MalfunctionUrgentEngine Problems30–120 minutes for initial diagnosisP0481 indicates a fault related to cooling fan 2 control circuit malfunction. Learn the likely causes and a practical diagnostic order before replacing parts.P0482Cooling Fan 3 Control Circuit MalfunctionUrgentEngine Problems30–120 minutes for initial diagnosisP0482 indicates a fault related to cooling fan 3 control circuit malfunction. Learn the likely causes and a practical diagnostic order before replacing parts.P0483Cooling Fan Rationality Check MalfunctionUrgentEngine Problems30–120 minutes for initial diagnosisP0483 indicates a fault related to cooling fan rationality check malfunction. Learn the likely causes and a practical diagnostic order before replacing parts.P0484Cooling Fan Circuit Over CurrentUrgentEngine Problems30–120 minutes for initial diagnosisP0484 indicates a fault related to cooling fan circuit over current. Learn the likely causes and a practical diagnostic order before replacing parts.P0485Cooling Fan Power/Ground Circuit MalfunctionUrgentEngine Problems30–120 minutes for initial diagnosisP0485 indicates a fault related to cooling fan power/ground circuit malfunction. Learn the likely causes and a practical diagnostic order before replacing parts.P0493Fan OverspeedUrgentEngine Problems30–120 minutes for initial diagnosisP0493 relates to fan overspeed. Check the fault conditions and vehicle-specific procedure before replacing parts.P0495Fan 1 OverspeedUrgentEngine Problems30–120 minutes for initial diagnosisP0495 relates to fan 1 overspeed. Check the fault conditions and vehicle-specific procedure before replacing parts.P0520Engine Oil Pressure Sensor/Switch CircuitUrgentEngine Problems30–120 minutes for initial diagnosisP0520 indicates a fault related to engine oil pressure sensor/switch circuit. Learn the likely causes and a practical diagnostic order before replacing parts.P0522Engine Oil Pressure Sensor/Switch Low VoltageUrgentEngine Problems30–120 minutes for initial diagnosisP0522 indicates a fault related to engine oil pressure sensor/switch low voltage. Learn the likely causes and a practical diagnostic order before replacing parts.P0523Engine Oil Pressure Sensor/Switch High VoltageUrgentEngine Problems30–120 minutes for initial diagnosisP0523 indicates a fault related to engine oil pressure sensor/switch high voltage. Learn the likely causes and a practical diagnostic order before replacing parts.P0524Engine Oil Pressure Too LowUrgentEngine Problems30–120 minutes for initial diagnosisP0524 indicates a fault related to engine oil pressure too low. Learn the likely causes and a practical diagnostic order before replacing parts.P0550Power Steering Pressure Sensor Circuit MalfunctionUrgentSensors & Electronics30–120 minutes for initial diagnosisP0550 indicates a fault related to power steering pressure sensor circuit malfunction. Learn the likely causes and a practical diagnostic order before replacing parts.P0551Power Steering Pressure Sensor Circuit Range/PerformanceUrgentSensors & Electronics30–120 minutes for initial diagnosisP0551 indicates a fault related to power steering pressure sensor circuit range/performance. Learn the likely causes and a practical diagnostic order before replacing parts.P0552Power Steering Pressure Sensor Circuit Low InputUrgentSensors & Electronics30–120 minutes for initial diagnosisP0552 indicates a fault related to power steering pressure sensor circuit low input. Learn the likely causes and a practical diagnostic order before replacing parts.P0553Power Steering Pressure Sensor Circuit High InputUrgentSensors & Electronics30–120 minutes for initial diagnosisP0553 indicates a fault related to power steering pressure sensor circuit high input. Learn the likely causes and a practical diagnostic order before replacing parts.