Diagnostic library
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Search the code from your scanner, then narrow the library by system, severity, or code family.
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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These are generic OBD2 definitions. Exact make, model, engine, and year compatibility will appear after vehicle-fitment data is added.
Diagnostic codes
Showing 1777–1800 of 2110
P2B90Turbocharger/Supercharger B Temperature Sensor Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2B91Turbocharger/Supercharger B Temperature Sensor Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2B92Turbocharger/Supercharger B Temperature Sensor Circuit Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2B93Wastegate Position Sensor A Exceeded Learning LimitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2B94Wastegate Position Sensor B Exceeded Learning LimitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2B97Exhaust Pressure Control Valve A Position Exceeded Learning LimitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2B98Exhaust Pressure Control Valve A Supply LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2B99Exhaust Pressure Control Valve A Driver Current/Temperature Too HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2B9AReductant Quality Sensor Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BA7NOx Exceedence - Empty Reagent TankCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BA8NOx Exceedence - Interruption of Reagent Dosing ActivityCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BA9NOx Exceedence - Insufficient Reagent QualityCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BAANOx Exceedence - Low Reagent ConsumptionCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BADNOx Exceedence - Root Cause UnknownCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BAENOx Exceedence - NOx control monitoring systemCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BAFNOx System Driver Inducement ActiveCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BBBTurbocharger/Supercharger Bypass Valve A Position Sensor CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BBCTurbocharger/Supercharger Bypass Valve A Position Sensor Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BBDTurbocharger/Supercharger Bypass Valve A Position Sensor Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BBETurbocharger/Supercharger Bypass Valve A Position Exceeded Learning LimitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BC0Turbocharger/Supercharger Bypass Valve A Driver Current/Temperature Too HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BD2Exhaust Aftertreatment System A LeakCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BD3Exhaust Aftertreatment System B LeakCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2BF4Exhaust Flow Control Valve A Position CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosis