Diagnostic library
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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 169–192 of 1049
P03A6Cylinder 2 Pressure Variation LowCheck soonEngine Problems30–120 minutes for initial diagnosisP03A7Cylinder 2 Pressure Variation HighCheck soonEngine Problems30–120 minutes for initial diagnosisP03A8Cylinder 2 Combustion PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP03A9Cylinder 3 Pressure Sensor CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP03AACylinder 3 Pressure Sensor Circuit Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP03ABCylinder 3 Pressure Sensor Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP03ACCylinder 3 Pressure Sensor Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP03ADCylinder 3 Pressure Sensor Circuit Intermittent/ErraticCheck soonEngine Problems30–120 minutes for initial diagnosisP03AECylinder 3 Pressure Too LowCheck soonEngine Problems30–120 minutes for initial diagnosisP03AFCylinder 3 Pressure Too HighCheck soonEngine Problems30–120 minutes for initial diagnosisP03B0Cylinder 3 Pressure Variation LowCheck soonEngine Problems30–120 minutes for initial diagnosisP03B1Cylinder 3 Pressure Variation HighCheck soonEngine Problems30–120 minutes for initial diagnosisP03B2Cylinder 3 Combustion PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP03B3Cylinder 4 Pressure Sensor CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP03B4Cylinder 4 Pressure Sensor Circuit Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP03B5Cylinder 4 Pressure Sensor Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP03B6Cylinder 4 Pressure Sensor Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP03B7Cylinder 4 Pressure Sensor Circuit Intermittent/ErraticCheck soonEngine Problems30–120 minutes for initial diagnosisP03B8Cylinder 4 Pressure Too LowCheck soonEngine Problems30–120 minutes for initial diagnosisP03B9Cylinder 4 Pressure Too HighCheck soonEngine Problems30–120 minutes for initial diagnosisP03BACylinder 4 Pressure Variation LowCheck soonEngine Problems30–120 minutes for initial diagnosisP03BBCylinder 4 Pressure Variation HighCheck soonEngine Problems30–120 minutes for initial diagnosisP03BCCylinder 4 Combustion PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP03BDCylinder 5 Pressure Sensor CircuitCheck soonEngine Problems30–120 minutes for initial diagnosis