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9,253 diagnostic guides
Find codes by symptomChoose what you notice to search matching code guides.
Rough idle or shakingVibration while stoppedHard to startLong cranking or no-startEngine stallsCuts out at idle or on the roadHesitates or loses powerSlow response when acceleratingBattery light is onCharging system warningHarsh 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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Diagnostic codes
Showing 193–216 of 515
P2099Post Catalyst Fuel Trim System Too Rich Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP20A0Reductant Purge Control Valve A Circuit /OpenCheck soonEmissions System30–120 minutes for initial diagnosisP20A1Reductant Purge Control Valve A PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP20A2Reductant Purge Control Valve A Circuit LowCheck soonEmissions System30–120 minutes for initial diagnosisP20A3Reductant Purge Control Valve A Circuit HighCheck soonEmissions System30–120 minutes for initial diagnosisP20A4Reductant Purge Control Valve A Stuck OpenCheck soonEmissions System30–120 minutes for initial diagnosisP20A5Reductant Purge Control Valve A Stuck ClosedCheck soonEmissions System30–120 minutes for initial diagnosisP20E2Exhaust Gas Temperature Sensor 1/2 Correlation Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP20E3Exhaust Gas Temperature Sensor 1/3 Correlation Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP20E4Exhaust Gas Temperature Sensor 2/3 Correlation Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP20E5Exhaust Gas Temperature Sensor 1/2 Correlation Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP20ECSCR NOx Catalyst - Over Temperature Bank 1UrgentEmissions System30–120 minutes for initial diagnosisP20EDSCR NOx Pre-Catalyst - Over Temperature Bank 1UrgentEmissions System30–120 minutes for initial diagnosisP20EESCR NOx Catalyst Efficiency Below Threshold Bank 1 Catalyst 1Low priorityEmissions System30–120 minutes for initial diagnosisP20EFSCR NOx Pre- Catalyst Efficiency Below Threshold Bank 1Low priorityEmissions System30–120 minutes for initial diagnosisP20F0SCR NOx Catalyst - Over Temperature Bank 2UrgentEmissions System30–120 minutes for initial diagnosisP20F1SCR NOx Pre-Catalyst - Over Temperature Bank 2UrgentEmissions System30–120 minutes for initial diagnosisP20F2SCR NOx Catalyst Efficiency Below Threshold Bank 2Low priorityEmissions System30–120 minutes for initial diagnosisP20F3SCR NOx Pre- Catalyst Efficiency Below Threshold Bank 2Low priorityEmissions System30–120 minutes for initial diagnosisP213AEGR Throttle Control Circuit B /OpenCheck soonEmissions System30–120 minutes for initial diagnosisP213BEGR Throttle Control Circuit B Range/PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP213CEGR Throttle Control Circuit B LowCheck soonEmissions System30–120 minutes for initial diagnosisP213DEGR Throttle Control Circuit B HighCheck soonEmissions System30–120 minutes for initial diagnosisP2141EGR Throttle Control Circuit A LowCheck soonEmissions System30–120 minutes for initial diagnosis