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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 1393–1416 of 1939

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P25B4Turbocharger/Supercharger Wastegate A Stuck ClosedCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25B4 relates to turbocharger/supercharger wastegate a stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P25B5Turbocharger/Supercharger Wastegate B Stuck OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25B5 relates to turbocharger/supercharger wastegate b stuck open. Check the fault conditions and vehicle-specific procedure before replacing parts.P25B6Turbocharger/Supercharger Wastegate B Stuck ClosedCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25B6 relates to turbocharger/supercharger wastegate b stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P25B7Auxiliary Ignition Switch On/Start Position CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25B7 relates to auxiliary ignition switch on/start position circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P25B8Auxiliary Ignition Switch On/Start Position Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25B8 relates to auxiliary ignition switch on/start position circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P25B9Auxiliary Ignition Switch On/Start Position Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25B9 relates to auxiliary ignition switch on/start position circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P25BARegeneration Control Switch Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25BA relates to regeneration control switch circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P25BBRegeneration Control Switch Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25BB relates to regeneration control switch circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P25BCRegeneration Control Switch Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25BC relates to regeneration control switch circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P25C4Brake Booster Temperature Sensor A CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25C4 relates to brake booster temperature sensor a circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P25C5Brake Booster Temperature Sensor A Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25C5 relates to brake booster temperature sensor a circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P25C6Brake Booster Temperature Sensor A Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25C6 relates to brake booster temperature sensor a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P25C7Brake Booster Temperature Sensor A Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25C7 relates to brake booster temperature sensor a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P25C8Brake Booster Temperature Sensor A Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25C8 relates to brake booster temperature sensor a circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P25C9Brake System Control Module B Requested MIL IlluminationCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25C9 relates to brake system control module b requested mil illumination. Check the fault conditions and vehicle-specific procedure before replacing parts.P25D6Exhaust Heat Exchanger Exhaust Bypass Valve A Position Sensor Stop PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25D6 relates to exhaust heat exchanger exhaust bypass valve a position sensor stop performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P25EEVacuum Pump Control Circuit B/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25EE relates to vacuum pump control circuit b/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P25EFVacuum Pump Control Circuit B Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25EF relates to vacuum pump control circuit b range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P25F0Vacuum Pump Control Circuit B LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25F0 relates to vacuum pump control circuit b low. Check the fault conditions and vehicle-specific procedure before replacing parts.P25F1Vacuum Pump Control Circuit B HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25F1 relates to vacuum pump control circuit b high. Check the fault conditions and vehicle-specific procedure before replacing parts.P25F2Turbocharger/Supercharger Boost Sensor C CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25F2 relates to turbocharger/supercharger boost sensor c circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P25F3Turbocharger/Supercharger Boost Sensor C Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25F3 relates to turbocharger/supercharger boost sensor c circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P25F4Turbocharger/Supercharger Boost Sensor C Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25F4 relates to turbocharger/supercharger boost sensor c circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P25F5Turbocharger/Supercharger Boost Sensor C Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25F5 relates to turbocharger/supercharger boost sensor c circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.