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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

FiltersSeverity · family

Severity

All severities9253 Low priority305 Check soon8256 Urgent621

Code family

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 6385–6408 of 9253

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P28B4Cylinder 10 Ion Current Sense CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP28B4 relates to cylinder 10 ion current sense circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P28B5Cylinder 10 Ion Current Sense Circuit Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP28B5 relates to cylinder 10 ion current sense circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P28B6Cylinder 10 Ion Current Sense Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP28B6 relates to cylinder 10 ion current sense circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P28B7Cylinder 10 Ion Current Sense Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP28B7 relates to cylinder 10 ion current sense circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P28B8Cylinder 11 Ion Current Sense CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP28B8 relates to cylinder 11 ion current sense circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P28B9Cylinder 11 Ion Current Sense Circuit Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP28B9 relates to cylinder 11 ion current sense circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P28BACylinder 11 Ion Current Sense Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP28BA relates to cylinder 11 ion current sense circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P28BBCylinder 11 Ion Current Sense Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP28BB relates to cylinder 11 ion current sense circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P28BCCylinder 12 Ion Current Sense CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP28BC relates to cylinder 12 ion current sense circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P28BDCylinder 12 Ion Current Sense Circuit Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP28BD relates to cylinder 12 ion current sense circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P28BECylinder 12 Ion Current Sense Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP28BE relates to cylinder 12 ion current sense circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P28BFCylinder 12 Ion Current Sense Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP28BF relates to cylinder 12 ion current sense circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P28C0Ion Sense Module Supply Voltage CircuitCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP28C0 relates to ion sense module supply voltage circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P28C1Ion Sense Module Supply Voltage LowCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP28C1 relates to ion sense module supply voltage low. Check the fault conditions and vehicle-specific procedure before replacing parts.P28C2Ion Sense Module Supply Voltage HighCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP28C2 relates to ion sense module supply voltage high. Check the fault conditions and vehicle-specific procedure before replacing parts.P28C3EVAP System High Load Purge Line B PerformanceLow priorityEmissions System30–120 minutes for initial diagnosisP28C3 relates to evap system high load purge line b performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P28C4Clutch A Motor Phase U-V-W Circuit LowCheck soonTransmission Issues30–120 minutes for initial diagnosisP28C4 relates to clutch a motor phase u-v-w circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P28C5Clutch A Motor Phase U-V-W Circuit HighCheck soonTransmission Issues30–120 minutes for initial diagnosisP28C5 relates to clutch a motor phase u-v-w circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P28C6Clutch A Motor Phase U-V-W Circuit/OpenCheck soonTransmission Issues30–120 minutes for initial diagnosisP28C6 relates to clutch a motor phase u-v-w circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P28C7Clutch A Motor Phase U-V-W PerformanceCheck soonTransmission Issues30–120 minutes for initial diagnosisP28C7 relates to clutch a motor phase u-v-w performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P28C8Clutch A Pump Motor PerformanceCheck soonTransmission Issues30–120 minutes for initial diagnosisP28C8 relates to clutch a pump motor performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P28C9Clutch A Motor OverspeedUrgentTransmission Issues30–120 minutes for initial diagnosisP28C9 relates to clutch a motor overspeed. Check the fault conditions and vehicle-specific procedure before replacing parts.P28CAClutch A Motor UnderspeedCheck soonTransmission Issues30–120 minutes for initial diagnosisP28CA relates to clutch a motor underspeed. Check the fault conditions and vehicle-specific procedure before replacing parts.P28CBClutch A Motor Position Sensor Circuit/OpenCheck soonTransmission Issues30–120 minutes for initial diagnosisP28CB relates to clutch a motor position sensor circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.