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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 4465–4488 of 6682
P25B9Auxiliary Ignition Switch On/Start Position Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25BARegeneration Control Switch Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25BBRegeneration Control Switch Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25BCRegeneration Control Switch Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25BDUnmetered Fuel - Forced Engine ShutdownCheck soonFuel System30–120 minutes for initial diagnosisP25BEAlternative Fuel Disable Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP25BFAlternative Fuel Disable Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP25C0Alternative Fuel Disable Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP25C1Alternative Fuel Disable Signal CircuitCheck soonFuel System30–120 minutes for initial diagnosisP25C2Alternative Fuel Disable Signal Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP25C3Alternative Fuel Disable Signal Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP25C4Brake Booster Temperature Sensor A CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25C5Brake Booster Temperature Sensor A Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25C6Brake Booster Temperature Sensor A Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25C7Brake Booster Temperature Sensor A Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25C8Brake Booster Temperature Sensor A Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25C9Brake System Control Module B Requested MIL IlluminationCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25CAIntake Camshaft Actuator Park Lock Control Circuit/Open Bank 1Check soonEngine Problems30–120 minutes for initial diagnosisP25CBIntake Camshaft Actuator Park Lock Control Circuit Low Bank 1Check soonEngine Problems30–120 minutes for initial diagnosisP25CCIntake Camshaft Actuator Park Lock Control Circuit High Bank 1Check soonEngine Problems30–120 minutes for initial diagnosisP25CDIntake Camshaft Actuator Park Lock Control Circuit/Open Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP25CEIntake Camshaft Actuator Park Lock Control Circuit Low Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP25CFIntake Camshaft Actuator Park Lock Control Circuit High Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP25D0Exhaust Camshaft Actuator Park Lock Control Circuit/Open Bank 1Check soonEngine Problems30–120 minutes for initial diagnosis