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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 5425–5448 of 6682

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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.P2AACDiesel Fuel Presence Sensor CircuitCheck soonFuel System30–120 minutes for initial diagnosisP2AAC relates to diesel fuel presence sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AADDiesel Fuel Presence Sensor Circuit Range/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2AAD relates to diesel fuel presence sensor circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AAEDiesel Fuel Presence Sensor Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP2AAE relates to diesel fuel presence sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AAFDiesel Fuel Presence Sensor Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2AAF relates to diesel fuel presence sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AB0Particulate Matter Sensor Processor PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP2AB0 relates to particulate matter sensor processor performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AB1Catalyst Heater Control Module PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP2AB1 relates to catalyst heater control module performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AB2Catalyst Heater Control Module Supply VoltageCheck soonEmissions System30–120 minutes for initial diagnosisP2AB2 relates to catalyst heater control module supply voltage. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AB3Cold Start Intake Manifold Runner Control Stuck Open Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2AB3 relates to cold start intake manifold runner control stuck open bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AB4Cold Start Intake Manifold Runner Control Stuck Open Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2AB4 relates to cold start intake manifold runner control stuck open bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AB5Cold Start Intake Manifold Runner Control Stuck Closed Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2AB5 relates to cold start intake manifold runner control stuck closed bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AB6Cold Start Intake Manifold Runner Control Stuck Closed Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2AB6 relates to cold start intake manifold runner control stuck closed bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AB7Wastegate Position Sensor A CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2AB7 relates to wastegate position sensor a circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AB8Wastegate Position Sensor A Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2AB8 relates to wastegate position sensor a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AB9Wastegate Position Sensor A Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2AB9 relates to wastegate position sensor a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2ABAWastegate Position Sensor B CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2ABA relates to wastegate position sensor b circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2ABBWastegate Position Sensor B Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2ABB relates to wastegate position sensor b circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2ABCWastegate Position Sensor B Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2ABC relates to wastegate position sensor b circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2ABDTurbocharger/Supercharger Wastegate Actuator A Driver Current/Temperature Too HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2ABD relates to turbocharger/supercharger wastegate actuator a driver current/temperature too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2ABETurbocharger/Supercharger Wastegate Actuator B Driver Current/Temperature Too HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2ABE relates to turbocharger/supercharger wastegate actuator b driver current/temperature too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2ABFIntake Air O2 Sensor Reference Voltage Circuit/Open Bank 1Check soonElectrical & Charging System30–120 minutes for initial diagnosisP2ABF relates to intake air o2 sensor reference voltage circuit/open bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AC0Intake Air O2 Sensor Reference Voltage Circuit Range/Performance Bank 1Check soonElectrical & Charging System30–120 minutes for initial diagnosisP2AC0 relates to intake air o2 sensor reference voltage circuit range/performance bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AC1Intake Air O2 Sensor Reference Voltage Circuit Low Bank 1Check soonElectrical & Charging System30–120 minutes for initial diagnosisP2AC1 relates to intake air o2 sensor reference voltage circuit low bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2AC2Intake Air O2 Sensor Reference Voltage Circuit High Bank 1Check soonElectrical & Charging System30–120 minutes for initial diagnosisP2AC2 relates to intake air o2 sensor reference voltage circuit high bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.