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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 169–192 of 1049

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P03A6Cylinder 2 Pressure Variation LowCheck soonEngine Problems30–120 minutes for initial diagnosisP03A6 relates to cylinder 2 pressure variation low. Check the fault conditions and vehicle-specific procedure before replacing parts.P03A7Cylinder 2 Pressure Variation HighCheck soonEngine Problems30–120 minutes for initial diagnosisP03A7 relates to cylinder 2 pressure variation high. Check the fault conditions and vehicle-specific procedure before replacing parts.P03A8Cylinder 2 Combustion PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP03A8 relates to cylinder 2 combustion performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P03A9Cylinder 3 Pressure Sensor CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP03A9 relates to cylinder 3 pressure sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P03AACylinder 3 Pressure Sensor Circuit Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP03AA relates to cylinder 3 pressure sensor circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P03ABCylinder 3 Pressure Sensor Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP03AB relates to cylinder 3 pressure sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P03ACCylinder 3 Pressure Sensor Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP03AC relates to cylinder 3 pressure sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P03ADCylinder 3 Pressure Sensor Circuit Intermittent/ErraticCheck soonEngine Problems30–120 minutes for initial diagnosisP03AD relates to cylinder 3 pressure sensor circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P03AECylinder 3 Pressure Too LowCheck soonEngine Problems30–120 minutes for initial diagnosisP03AE relates to cylinder 3 pressure too low. Check the fault conditions and vehicle-specific procedure before replacing parts.P03AFCylinder 3 Pressure Too HighCheck soonEngine Problems30–120 minutes for initial diagnosisP03AF relates to cylinder 3 pressure too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P03B0Cylinder 3 Pressure Variation LowCheck soonEngine Problems30–120 minutes for initial diagnosisP03B0 relates to cylinder 3 pressure variation low. Check the fault conditions and vehicle-specific procedure before replacing parts.P03B1Cylinder 3 Pressure Variation HighCheck soonEngine Problems30–120 minutes for initial diagnosisP03B1 relates to cylinder 3 pressure variation high. Check the fault conditions and vehicle-specific procedure before replacing parts.P03B2Cylinder 3 Combustion PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP03B2 relates to cylinder 3 combustion performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P03B3Cylinder 4 Pressure Sensor CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP03B3 relates to cylinder 4 pressure sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P03B4Cylinder 4 Pressure Sensor Circuit Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP03B4 relates to cylinder 4 pressure sensor circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P03B5Cylinder 4 Pressure Sensor Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP03B5 relates to cylinder 4 pressure sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P03B6Cylinder 4 Pressure Sensor Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP03B6 relates to cylinder 4 pressure sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P03B7Cylinder 4 Pressure Sensor Circuit Intermittent/ErraticCheck soonEngine Problems30–120 minutes for initial diagnosisP03B7 relates to cylinder 4 pressure sensor circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P03B8Cylinder 4 Pressure Too LowCheck soonEngine Problems30–120 minutes for initial diagnosisP03B8 relates to cylinder 4 pressure too low. Check the fault conditions and vehicle-specific procedure before replacing parts.P03B9Cylinder 4 Pressure Too HighCheck soonEngine Problems30–120 minutes for initial diagnosisP03B9 relates to cylinder 4 pressure too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P03BACylinder 4 Pressure Variation LowCheck soonEngine Problems30–120 minutes for initial diagnosisP03BA relates to cylinder 4 pressure variation low. Check the fault conditions and vehicle-specific procedure before replacing parts.P03BBCylinder 4 Pressure Variation HighCheck soonEngine Problems30–120 minutes for initial diagnosisP03BB relates to cylinder 4 pressure variation high. Check the fault conditions and vehicle-specific procedure before replacing parts.P03BCCylinder 4 Combustion PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP03BC relates to cylinder 4 combustion performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P03BDCylinder 5 Pressure Sensor CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP03BD relates to cylinder 5 pressure sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.