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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

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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 1153–1176 of 7353

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P051CCrankcase Pressure Sensor A Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP051C relates to crankcase pressure sensor a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P051DCrankcase Pressure Sensor A Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP051D relates to crankcase pressure sensor a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P051ECrankcase Pressure Sensor A Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP051E relates to crankcase pressure sensor a circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P051FPCV Filter RestrictionCheck soonSensors & Electronics30–120 minutes for initial diagnosisP051F relates to pcv filter restriction. 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.P0521Engine Oil Pressure Sensor/Switch Range/PerformanceEngine ProblemsFix P0521 oil pressure sensor code. Learn what causes oil pressure sensor faults and when low oil pressure is real.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.P0525Cruise Control Servo Control Circuit Range/PerformanceLow prioritySensors & Electronics30–120 minutes for initial diagnosisP0525 relates to cruise control servo control circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0526Fan Speed Sensor CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP0526 relates to fan speed sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P0527Fan Speed Sensor Circuit Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP0527 relates to fan speed sensor circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0528Fan Speed Sensor Circuit No SignalCheck soonEngine Problems30–120 minutes for initial diagnosisP0528 relates to fan speed sensor circuit no signal. Check the fault conditions and vehicle-specific procedure before replacing parts.P0529Fan Speed Sensor Circuit IntermittentCheck soonEngine Problems30–120 minutes for initial diagnosisP0529 relates to fan speed sensor circuit intermittent. Check the fault conditions and vehicle-specific procedure before replacing parts.P052ACold Start A Camshaft Position Timing Over-Advanced Bank 1Check soonEngine Problems30–120 minutes for initial diagnosisP052A relates to cold start a camshaft position timing over-advanced bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P052BCold Start A Camshaft Position Timing Over-Retarded Bank 1Check soonEngine Problems30–120 minutes for initial diagnosisP052B relates to cold start a camshaft position timing over-retarded bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P052CCold Start A Camshaft Position Timing Over-Advanced Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP052C relates to cold start a camshaft position timing over-advanced bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P052DCold Start A Camshaft Position Timing Over-Retarded Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP052D relates to cold start a camshaft position timing over-retarded bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P052EPCV Regulator Valve PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP052E relates to pcv regulator valve performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P052FGlow Plug Control Module 1 System VoltageCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP052F relates to glow plug control module 1 system voltage. Check the fault conditions and vehicle-specific procedure before replacing parts.P0530A/C Refrigerant Pressure Sensor CircuitLow prioritySensors & Electronics30–120 minutes for initial diagnosisP0530 indicates a fault related to a/c refrigerant pressure sensor circuit. Learn the likely causes and a practical diagnostic order before replacing parts.P0531A/C Refrigerant Pressure Sensor Range/PerformanceLow prioritySensors & Electronics30–120 minutes for initial diagnosisP0531 indicates a fault related to a/c refrigerant pressure sensor range/performance. Learn the likely causes and a practical diagnostic order before replacing parts.P0532A/C Refrigerant Pressure Sensor Circuit LowLow prioritySensors & Electronics30–120 minutes for initial diagnosisP0532 indicates a fault related to a/c refrigerant pressure sensor circuit low. Learn the likely causes and a practical diagnostic order before replacing parts.P0533A/C Refrigerant Pressure Sensor Circuit HighLow prioritySensors & Electronics30–120 minutes for initial diagnosisP0533 indicates a fault related to a/c refrigerant pressure sensor circuit high. Learn the likely causes and a practical diagnostic order before replacing parts.