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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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Diagnostic codes

Showing 3481–3504 of 6682

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P21A2Cylinder 7 Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP21A2 relates to cylinder 7 air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P21A3Cylinder 8 Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP21A3 relates to cylinder 8 air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P21A4Cylinder 9 Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP21A4 relates to cylinder 9 air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P21A5Cylinder 10 Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP21A5 relates to cylinder 10 air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P21A6Cylinder 11 Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP21A6 relates to cylinder 11 air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P21A7Cylinder 12 Air-Fuel Ratio ImbalanceCheck soonFuel System30–120 minutes for initial diagnosisP21A7 relates to cylinder 12 air-fuel ratio imbalance. Check the fault conditions and vehicle-specific procedure before replacing parts.P21A8Reductant Level Sensor B CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP21A8 relates to reductant level sensor b circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P21A9Reductant Level Sensor B Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP21A9 relates to reductant level sensor b circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P21AAReductant Level Sensor B Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP21AA relates to reductant level sensor b circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P21ABReductant Level Sensor B Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP21AB relates to reductant level sensor b circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P21ACReductant Level Sensor B Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP21AC relates to reductant level sensor b circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P21ADReductant Level Sensor C CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP21AD relates to reductant level sensor c circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P21AEReductant Level Sensor C Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP21AE relates to reductant level sensor c circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P21AFReductant Level Sensor C Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP21AF relates to reductant level sensor c circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P21B0Reductant Level Sensor C Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP21B0 relates to reductant level sensor c circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P21B1Reductant Level Sensor C Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP21B1 relates to reductant level sensor c circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P21B2Excessive Time To Enter Closed Loop NOx Adsorber ControlCheck soonSensors & Electronics30–120 minutes for initial diagnosisP21B2 relates to excessive time to enter closed loop nox adsorber control. Check the fault conditions and vehicle-specific procedure before replacing parts.P21B3Closed Loop NOx Adsorber Control At Limit - Too HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP21B3 relates to closed loop nox adsorber control at limit - too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P21B6Cold Start Cylinder 1 Injection TimingCheck soonFuel System30–120 minutes for initial diagnosisP21B6 relates to cold start cylinder 1 injection timing. Check the fault conditions and vehicle-specific procedure before replacing parts.P21B7Cold Start Cylinder 2 Injection TimingCheck soonFuel System30–120 minutes for initial diagnosisP21B7 relates to cold start cylinder 2 injection timing. Check the fault conditions and vehicle-specific procedure before replacing parts.P21B8Cold Start Cylinder 3 Injection TimingCheck soonFuel System30–120 minutes for initial diagnosisP21B8 relates to cold start cylinder 3 injection timing. Check the fault conditions and vehicle-specific procedure before replacing parts.P21B9Cold Start Cylinder 4 Injection TimingCheck soonFuel System30–120 minutes for initial diagnosisP21B9 relates to cold start cylinder 4 injection timing. Check the fault conditions and vehicle-specific procedure before replacing parts.P21BACold Start Cylinder 5 Injection TimingCheck soonFuel System30–120 minutes for initial diagnosisP21BA relates to cold start cylinder 5 injection timing. Check the fault conditions and vehicle-specific procedure before replacing parts.P21BBCold Start Cylinder 6 Injection TimingCheck soonFuel System30–120 minutes for initial diagnosisP21BB relates to cold start cylinder 6 injection timing. Check the fault conditions and vehicle-specific procedure before replacing parts.