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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.

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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 1129–1152 of 2110

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P2259AIR System Control B Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2259 relates to air system control b circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P225ANOx Sensor Calibration Memory Bank 1 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP225A relates to nox sensor calibration memory bank 1 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P225BNOx Sensor Calibration Memory Bank 1 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP225B relates to nox sensor calibration memory bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P225CNOx Sensor Performance - Signal Biased/Stuck High Bank 1 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP225C relates to nox sensor performance - signal biased/stuck high bank 1 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P225DNOx Sensor Performance - Signal Biased/Stuck Low Bank 1 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP225D relates to nox sensor performance - signal biased/stuck low bank 1 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P225ENOx Sensor Performance - Signal Biased/Stuck High Bank 1 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP225E relates to nox sensor performance - signal biased/stuck high bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P225FNOx Sensor Performance - Signal Biased/Stuck Low Bank 1 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP225F relates to nox sensor performance - signal biased/stuck low bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2260AIR System Control B Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2260 relates to air system control b circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2261Turbocharger/Supercharger Bypass Valve A - MechanicalCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2261 relates to turbocharger/supercharger bypass valve a - mechanical. Check the fault conditions and vehicle-specific procedure before replacing parts.P2262Turbocharger/Supercharger Boost Pressure A Not Detected - MechanicalCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2262 relates to turbocharger/supercharger boost pressure a not detected - mechanical. Check the fault conditions and vehicle-specific procedure before replacing parts.P2263Turbocharger/Supercharger A Boost System PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2263 relates to turbocharger/supercharger a boost system performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P226BTurbocharger/Supercharger A Boost Pressure Too High - MechanicalCheck soonSensors & Electronics30–120 minutes for initial diagnosisP226B relates to turbocharger/supercharger a boost pressure too high - mechanical. Check the fault conditions and vehicle-specific procedure before replacing parts.P226CTurbocharger Boost Control A Slow ResponseCheck soonSensors & Electronics30–120 minutes for initial diagnosisP226C relates to turbocharger boost control a slow response. Check the fault conditions and vehicle-specific procedure before replacing parts.P226FTurbocharger Boost Control B Slow ResponseCheck soonSensors & Electronics30–120 minutes for initial diagnosisP226F relates to turbocharger boost control b slow response. Check the fault conditions and vehicle-specific procedure before replacing parts.P2270O2 Sensor Signal Biased/Stuck Lean Bank 1 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2270 relates to o2 sensor signal biased/stuck lean bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2271O2 Sensor Signal Biased/Stuck Rich Bank 1 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2271 relates to o2 sensor signal biased/stuck rich bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2272O2 Sensor Signal Biased/Stuck Lean Bank 2 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2272 relates to o2 sensor signal biased/stuck lean bank 2 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2273O2 Sensor Signal Biased/Stuck Rich Bank 2 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2273 relates to o2 sensor signal biased/stuck rich bank 2 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2274O2 Sensor Signal Biased/Stuck Lean Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP2274 relates to o2 sensor signal biased/stuck lean bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P2275O2 Sensor Signal Biased/Stuck Rich Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP2275 relates to o2 sensor signal biased/stuck rich bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P2276O2 Sensor Signal Biased/Stuck Lean Bank 2 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP2276 relates to o2 sensor signal biased/stuck lean bank 2 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P2277O2 Sensor Signal Biased/Stuck Rich Bank 2 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP2277 relates to o2 sensor signal biased/stuck rich bank 2 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P2278O2 Sensor Signals Swapped Bank 1 Sensor 3/Bank 2 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP2278 relates to o2 sensor signals swapped bank 1 sensor 3/bank 2 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P2279Intake Air System Leak Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2279 relates to intake air system leak bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.