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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 1–24 of 1939

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P0069Manifold Absolute Pressure–Barometric Pressure CorrelationCheck soonSensors & Electronics45–120 minutes for initial diagnosisP0069 means Manifold Absolute Pressure–Barometric Pressure Correlation. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.P0221Throttle/Pedal Position Sensor/Switch B Circuit Range/PerformanceCheck soonSensors & Electronics45–120 minutes for initial diagnosisP0221 means Throttle/Pedal Position Sensor/Switch B Circuit Range/Performance. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.P0235Turbocharger/Supercharger Boost Sensor A CircuitCheck soonSensors & Electronics45–120 minutes for initial diagnosisP0235 means Turbocharger/Supercharger Boost Sensor A Circuit. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.P0008Engine Position System Performance Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP0008 relates to engine position system performance bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P0009Engine Position System Performance Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP0009 relates to engine position system performance bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P0026Intake Valve Control Solenoid Circuit Range/Performance Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP0026 relates to intake valve control solenoid circuit range/performance bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P0027Exhaust Valve Control Solenoid Circuit Range/Performance Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP0027 relates to exhaust valve control solenoid circuit range/performance bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P0028Intake Valve Control Solenoid Circuit Range/Performance Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP0028 relates to intake valve control solenoid circuit range/performance bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P0029Exhaust Valve Control Solenoid Circuit Range/Performance Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP0029 relates to exhaust valve control solenoid circuit range/performance bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P0033Turbocharger/Supercharger Bypass Valve A Control CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0033 relates to turbocharger/supercharger bypass valve a control circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P0034Turbocharger/Supercharger Bypass Valve A Control Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0034 relates to turbocharger/supercharger bypass valve a control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0035Turbocharger/Supercharger Bypass Valve A Control Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0035 relates to turbocharger/supercharger bypass valve a control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0039Turbocharger/Supercharger Bypass Valve A Control Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0039 relates to turbocharger/supercharger bypass valve a control circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P003ATurbocharger/Supercharger Boost Control A Position Exceeded Learning LimitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP003A relates to turbocharger/supercharger boost control a position exceeded learning limit. Check the fault conditions and vehicle-specific procedure before replacing parts.P003BTurbocharger/Supercharger Boost Control B Position Exceeded Learning LimitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP003B relates to turbocharger/supercharger boost control b position exceeded learning limit. Check the fault conditions and vehicle-specific procedure before replacing parts.P0040O2 Sensor Signals Swapped Bank 1 Sensor 1/Bank 2 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP0040 relates to o2 sensor signals swapped bank 1 sensor 1/bank 2 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P0041O2 Sensor Signals Swapped Bank 1 Sensor 2/Bank 2 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP0041 relates to o2 sensor signals swapped bank 1 sensor 2/bank 2 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P0045Turbocharger/Supercharger Boost Control A Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0045 relates to turbocharger/supercharger boost control a circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P0046Turbocharger/Supercharger Boost Control A Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0046 relates to turbocharger/supercharger boost control a circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0047Turbocharger/Supercharger Boost Control A Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0047 relates to turbocharger/supercharger boost control a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0048Turbocharger/Supercharger Boost Control A Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0048 relates to turbocharger/supercharger boost control a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P004ATurbocharger/Supercharger Boost Control B Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP004A relates to turbocharger/supercharger boost control b circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P004BTurbocharger/Supercharger Boost Control B Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP004B relates to turbocharger/supercharger boost control b circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P004CTurbocharger/Supercharger Boost Control B Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP004C relates to turbocharger/supercharger boost control b circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.