Diagnostic library
Find an OBD2 code
Search the code from your scanner, then narrow the library by system, severity, or code family.
9,253 diagnostic guides
Find codes by symptomChoose what you notice to search matching code guides.
Rough idle or shakingVibration while stoppedHard to startLong cranking or no-startEngine stallsCuts out at idle or on the roadHesitates or loses powerSlow response when acceleratingBattery light is onCharging system warningHarsh 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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These are generic OBD2 definitions. Exact make, model, engine, and year compatibility will appear after vehicle-fitment data is added.
Diagnostic codes
Showing 265–288 of 1049
P0508Idle Air Control System Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP0509Idle Air Control System Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP050BCold Start Ignition Timing PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP050CCold Start Engine Coolant Temperature PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP0511Idle Air Control CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP0520Engine Oil Pressure Sensor/Switch CircuitUrgentEngine Problems30–120 minutes for initial diagnosisP0521Engine Oil Pressure Sensor/Switch Range/PerformanceEngine ProblemsP0522Engine Oil Pressure Sensor/Switch Low VoltageUrgentEngine Problems30–120 minutes for initial diagnosisP0523Engine Oil Pressure Sensor/Switch High VoltageUrgentEngine Problems30–120 minutes for initial diagnosisP0524Engine Oil Pressure Too LowUrgentEngine Problems30–120 minutes for initial diagnosisP0526Fan Speed Sensor CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP0527Fan Speed Sensor Circuit Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP0528Fan Speed Sensor Circuit No SignalCheck soonEngine Problems30–120 minutes for initial diagnosisP0529Fan Speed Sensor Circuit IntermittentCheck soonEngine Problems30–120 minutes for initial diagnosisP052ACold Start A Camshaft Position Timing Over-Advanced Bank 1Check soonEngine Problems30–120 minutes for initial diagnosisP052BCold Start A Camshaft Position Timing Over-Retarded Bank 1Check soonEngine Problems30–120 minutes for initial diagnosisP052CCold Start A Camshaft Position Timing Over-Advanced Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP052DCold Start A Camshaft Position Timing Over-Retarded Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP054ACold Start B Camshaft Position Timing Over-Advanced Bank 1Check soonEngine Problems30–120 minutes for initial diagnosisP054BCold Start B Camshaft Position Timing Over-Retarded Bank 1Check soonEngine Problems30–120 minutes for initial diagnosisP054CCold Start B Camshaft Position Timing Over-Advanced Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP054DCold Start B Camshaft Position Timing Over-Retarded Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP055AEngine Oil Pressure Sensor/Switch B CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP055BEngine Oil Pressure Sensor/Switch B Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosis