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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.

Check soon 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 5449–5472 of 6682

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P2AC3Intake Air O2 Sensor Reference Voltage Circuit/Open Bank 2Check soonElectrical & Charging System30–120 minutes for initial diagnosisP2AC3 relates to intake air o2 sensor reference voltage circuit/open bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AC4Intake Air O2 Sensor Reference Voltage Circuit Range/Performance Bank 2Check soonElectrical & Charging System30–120 minutes for initial diagnosisP2AC4 relates to intake air o2 sensor reference voltage circuit range/performance bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AC5Intake Air O2 Sensor Reference Voltage Circuit Low Bank 2Check soonElectrical & Charging System30–120 minutes for initial diagnosisP2AC5 relates to intake air o2 sensor reference voltage circuit low bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AC6Intake Air O2 Sensor Reference Voltage Circuit High Bank 2Check soonElectrical & Charging System30–120 minutes for initial diagnosisP2AC6 relates to intake air o2 sensor reference voltage circuit high bank 2. 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.P2ACCReductant Temperature Sensor B CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2ACC relates to reductant temperature sensor b circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2ACDReductant Temperature Sensor B Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2ACD relates to reductant temperature sensor b circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2ACEReductant Temperature Sensor B Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2ACE relates to reductant temperature sensor b circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2ACFReductant Temperature Sensor B Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2ACF relates to reductant temperature sensor b circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AD0Reductant Temperature Sensor B Circuit IntermittentCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2AD0 relates to reductant temperature sensor b circuit intermittent. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AD1Throttle/Pedal Position Sensor/Switch C/G Voltage CorrelationCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP2AD1 relates to throttle/pedal position sensor/switch c/g voltage correlation. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AD2Throttle/Pedal Position Sensor/Switch B/G Voltage CorrelationCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP2AD2 relates to throttle/pedal position sensor/switch b/g voltage correlation. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AD3Throttle/Pedal Position Sensor/Switch A/G Voltage CorrelationCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP2AD3 relates to throttle/pedal position sensor/switch a/g voltage correlation. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AD4Intermediate System Voltage LowCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP2AD4 relates to intermediate system voltage low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AD5Intermediate System Voltage HighCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP2AD5 relates to intermediate system voltage high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AD6Reductant Pump Motor Position Sensor CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2AD6 relates to reductant pump motor position sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AD7Reductant Pump Motor Position Sensor Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2AD7 relates to reductant pump motor position sensor circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AD8Reductant Pump Motor Position Sensor Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2AD8 relates to reductant pump motor position sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AD9Reductant Pump Motor Position Sensor Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2AD9 relates to reductant pump motor position sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2ADAReductant Tank Temperature Sensor B Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2ADA relates to reductant tank temperature sensor b circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.