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9,253 diagnostic guides

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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.

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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 6217–6240 of 7353

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P2B9BVehicle Conditions Incorrect for Particulate Matter Sensor RegenerationCheck soonEmissions System30–120 minutes for initial diagnosisP2B9B relates to vehicle conditions incorrect for particulate matter sensor regeneration. Check the fault conditions and vehicle-specific procedure before replacing parts.P2B9CCoolant Pump A Stuck/StalledCheck soonEngine Problems30–120 minutes for initial diagnosisP2B9C relates to coolant pump a stuck/stalled. Check the fault conditions and vehicle-specific procedure before replacing parts.P2B9DCoolant Pump A Supply Voltage CircuitCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP2B9D relates to coolant pump a supply voltage circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2B9ECoolant Pump A Control Module OvertemperatureCheck soonEngine Problems30–120 minutes for initial diagnosisP2B9E relates to coolant pump a control module overtemperature. Check the fault conditions and vehicle-specific procedure before replacing parts.P2B9FCoolant Pump B UnderspeedCheck soonEngine Problems30–120 minutes for initial diagnosisP2B9F relates to coolant pump b underspeed. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BA0Coolant Pump C UnderspeedCheck soonEngine Problems30–120 minutes for initial diagnosisP2BA0 relates to coolant pump c underspeed. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BA1Coolant Pump D UnderspeedCheck soonEngine Problems30–120 minutes for initial diagnosisP2BA1 relates to coolant pump d underspeed. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BA2Engine Coolant Pump Stuck/StalledCheck soonEngine Problems30–120 minutes for initial diagnosisP2BA2 relates to engine coolant pump stuck/stalled. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BA3Starter/Generator Mechanical PerformanceCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP2BA3 relates to starter/generator mechanical performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BA4Catalyst Feedgas PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP2BA4 relates to catalyst feedgas performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BA5Particulate Filter Feedgas PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP2BA5 relates to particulate filter feedgas performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BA6NOx Exceedance - SCR NOx Catalyst PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP2BA6 relates to nox exceedance - scr nox catalyst performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BA7NOx Exceedence - Empty Reagent TankCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BA7 relates to nox exceedence - empty reagent tank. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BA8NOx Exceedence - Interruption of Reagent Dosing ActivityCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BA8 relates to nox exceedence - interruption of reagent dosing activity. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BA9NOx Exceedence - Insufficient Reagent QualityCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BA9 relates to nox exceedence - insufficient reagent quality. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BAANOx Exceedence - Low Reagent ConsumptionCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BAA relates to nox exceedence - low reagent consumption. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BABNOx Exceedence - Incorrect EGR FlowCheck soonEmissions System30–120 minutes for initial diagnosisP2BAB relates to nox exceedence - incorrect egr flow. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BACNOx Exceedence - Deactivation of EGRCheck soonEmissions System30–120 minutes for initial diagnosisP2BAC relates to nox exceedence - deactivation of egr. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BADNOx Exceedence - Root Cause UnknownCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BAD relates to nox exceedence - root cause unknown. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BAENOx Exceedence - NOx control monitoring systemCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BAE relates to nox exceedence - nox control monitoring system. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BAFNOx System Driver Inducement ActiveCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BAF relates to nox system driver inducement active. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BB0Alternative Fuel Consumption Too LowCheck soonFuel System30–120 minutes for initial diagnosisP2BB0 relates to alternative fuel consumption too low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BB1Alternative Fuel Consumption Too HighCheck soonFuel System30–120 minutes for initial diagnosisP2BB1 relates to alternative fuel consumption too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BB2Alternative Fuel Tank EmptyCheck soonFuel System30–120 minutes for initial diagnosisP2BB2 relates to alternative fuel tank empty. Check the fault conditions and vehicle-specific procedure before replacing parts.