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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 1033–1056 of 6682
P0548Exhaust Gas Temperature Sensor Circuit Low Bank 2 Sensor 1Check soonEmissions System30–120 minutes for initial diagnosisP0549Exhaust Gas Temperature Sensor Circuit High Bank 2 Sensor 1Check soonEmissions System30–120 minutes for initial diagnosisP054ACold Start B Camshaft Position Timing Over-Advanced Bank 1Check soonEngine Problems30–120 minutes for initial diagnosisP054BCold Start B Camshaft Position Timing Over-Retarded Bank 1Check soonEngine Problems30–120 minutes for initial diagnosisP054CCold Start B Camshaft Position Timing Over-Advanced Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP054DCold Start B Camshaft Position Timing Over-Retarded Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP054EIdle Control System - Fuel Quantity Lower Than ExpectedCheck soonFuel System30–120 minutes for initial diagnosisP054FIdle Control System - Fuel Quantity Higher Than ExpectedCheck soonFuel System30–120 minutes for initial diagnosisP0555Brake Booster Pressure Sensor CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0556Brake Booster Pressure Sensor Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0557Brake Booster Pressure Sensor Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0558Brake Booster Pressure Sensor Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0559Brake Booster Pressure Sensor Circuit IntermittentCheck soonSensors & Electronics30–120 minutes for initial diagnosisP055AEngine Oil Pressure Sensor/Switch B CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP055BEngine Oil Pressure Sensor/Switch B Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP055CEngine Oil Pressure Sensor/Switch B LowCheck soonEngine Problems30–120 minutes for initial diagnosisP055DEngine Oil Pressure Sensor/Switch B HighCheck soonEngine Problems30–120 minutes for initial diagnosisP055EOxygen Sensor Control Module System VoltageCheck soonEmissions System30–120 minutes for initial diagnosisP055FEngine Oil Pressure Out of RangeCheck soonEngine Problems30–120 minutes for initial diagnosisP0561System Voltage UnstableCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP056DReductant Control Module System VoltageCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP056ECold Start Turbocharger/Supercharger Boost Control A PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP056FCold Start Turbocharger/Supercharger Boost Control B PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP057ABrake Pedal Position Sensor A Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosis