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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.

Engine Problems P · Powertrain Clear all

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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 601–624 of 1049

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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.P2AA7Engine Coolant Bypass Valve B Position Sensor CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP2AA7 relates to engine coolant bypass valve b position sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AA8Engine Coolant Bypass Valve B Position Sensor Circuit Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP2AA8 relates to engine coolant bypass valve b position sensor circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AA9Engine Coolant Bypass Valve B Position Sensor Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP2AA9 relates to engine coolant bypass valve b position sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AAAEngine Coolant Bypass Valve B Position Sensor Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP2AAA relates to engine coolant bypass valve b position sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AABEngine Coolant Bypass Valve B Position Sensor Circuit Intermittent/ErraticCheck soonEngine Problems30–120 minutes for initial diagnosisP2AAB relates to engine coolant bypass valve b position sensor circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AC7Charge Air Cooler Coolant Temperature Sensor B CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP2AC7 relates to charge air cooler coolant temperature sensor b circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AC8Charge Air Cooler Coolant Temperature Sensor B Circuit Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP2AC8 relates to charge air cooler coolant temperature sensor b circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AC9Charge Air Cooler Coolant Temperature Sensor B Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP2AC9 relates to charge air cooler coolant temperature sensor b circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2ACACharge Air Cooler Coolant Temperature Sensor B Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP2ACA relates to charge air cooler coolant temperature sensor b circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2ACBCharge Air Cooler Coolant Temperature Sensor B Intermittent/ErraticCheck soonEngine Problems30–120 minutes for initial diagnosisP2ACB relates to charge air cooler coolant temperature sensor b intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AFCEngine Coolant Temperature Sensor 4 CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP2AFC relates to engine coolant temperature sensor 4 circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AFDEngine Coolant Temperature Sensor 4 Circuit Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP2AFD relates to engine coolant temperature sensor 4 circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AFEEngine Coolant Temperature Sensor 4 Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP2AFE relates to engine coolant temperature sensor 4 circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AFFEngine Coolant Temperature Sensor 4 Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP2AFF relates to engine coolant temperature sensor 4 circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2B20Hybrid/EV Electronics Coolant Temperature Sensor B CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP2B20 relates to hybrid/ev electronics coolant temperature sensor b circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2B21Hybrid/EV Electronics Coolant Temperature Sensor B Circuit Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP2B21 relates to hybrid/ev electronics coolant temperature sensor b circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2B22Hybrid/EV Electronics Coolant Temperature Sensor B Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP2B22 relates to hybrid/ev electronics coolant temperature sensor b circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2B23Hybrid/EV Electronics Coolant Temperature Sensor B Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP2B23 relates to hybrid/ev electronics coolant temperature sensor b circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.