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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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Severity

All severities9253 Low priority305 Check soon8256 Urgent621

Code family

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 1657–1680 of 1939

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P2B9AReductant Quality Sensor Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2B9A relates to reductant quality sensor circuit intermittent/erratic. 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.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.P2BBBTurbocharger/Supercharger Bypass Valve A Position Sensor CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BBB relates to turbocharger/supercharger bypass valve a position sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BBCTurbocharger/Supercharger Bypass Valve A Position Sensor Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BBC relates to turbocharger/supercharger bypass valve a position sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BBDTurbocharger/Supercharger Bypass Valve A Position Sensor Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BBD relates to turbocharger/supercharger bypass valve a position sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BBETurbocharger/Supercharger Bypass Valve A Position Exceeded Learning LimitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BBE relates to turbocharger/supercharger bypass valve a position exceeded learning limit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BC0Turbocharger/Supercharger Bypass Valve A Driver Current/Temperature Too HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BC0 relates to turbocharger/supercharger bypass valve a driver current/temperature too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BD2Exhaust Aftertreatment System A LeakCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BD2 relates to exhaust aftertreatment system a leak. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BD3Exhaust Aftertreatment System B LeakCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BD3 relates to exhaust aftertreatment system b leak. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BF4Exhaust Flow Control Valve A Position CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BF4 relates to exhaust flow control valve a position circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BF5Exhaust Flow Control Valve A Position Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BF5 relates to exhaust flow control valve a position circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BF6Exhaust Flow Control Valve A Position Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BF6 relates to exhaust flow control valve a position circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BF7Exhaust Flow Control Valve A Position Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BF7 relates to exhaust flow control valve a position circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BF8Exhaust Flow Control Valve B Control Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BF8 relates to exhaust flow control valve b control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BF9Exhaust Flow Control Valve B Control Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BF9 relates to exhaust flow control valve b control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BFAExhaust Flow Control Valve B Control Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BFA relates to exhaust flow control valve b control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BFBExhaust Flow Control Valve B Control PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BFB relates to exhaust flow control valve b control performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2BFCExhaust Flow Control Valve B Position CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BFC relates to exhaust flow control valve b position circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.