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9,253 diagnostic guides

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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 4969–4992 of 7353

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P25A4Fuel Mode Select Switch CircuitCheck soonFuel System30–120 minutes for initial diagnosisP25A4 relates to fuel mode select switch circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P25A5Fuel Mode Select Switch PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP25A5 relates to fuel mode select switch performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P25A6Fuel Mode Select Switch Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP25A6 relates to fuel mode select switch circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P25A7Fuel Mode Select Switch Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP25A7 relates to fuel mode select switch circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P25A8Fuel Mode Select Switch Circuit Intermittent/ErraticCheck soonFuel System30–120 minutes for initial diagnosisP25A8 relates to fuel mode select switch circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P25A9Piston Cooling Oil Control Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25A9 relates to piston cooling oil control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P25AAPiston Cooling Oil Control Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25AA relates to piston cooling oil control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P25ABPiston Cooling Oil Control Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25AB relates to piston cooling oil control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P25ACPiston Cooling Oil Control Circuit Performance/Stuck OffCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25AC relates to piston cooling oil control circuit performance/stuck off. Check the fault conditions and vehicle-specific procedure before replacing parts.P25ADPiston Cooling Oil Control Circuit Stuck OnCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25AD relates to piston cooling oil control circuit stuck on. Check the fault conditions and vehicle-specific procedure before replacing parts.P25AEPiston Cooling Oil Pressure Too LowUrgentEngine Problems30–120 minutes for initial diagnosisP25AE relates to piston cooling oil pressure too low. Check the fault conditions and vehicle-specific procedure before replacing parts.P25AFCoolant Temperature Control Module Requested MIL IlluminationCheck soonEngine Problems30–120 minutes for initial diagnosisP25AF relates to coolant temperature control module requested mil illumination. Check the fault conditions and vehicle-specific procedure before replacing parts.P25B0Fuel Level Sensor A StuckLow priorityFuel System30–120 minutes for initial diagnosisP25B0 relates to fuel level sensor a stuck. Check the fault conditions and vehicle-specific procedure before replacing parts.P25B1Fuel Level Sensor B StuckLow priorityFuel System30–120 minutes for initial diagnosisP25B1 relates to fuel level sensor b stuck. Check the fault conditions and vehicle-specific procedure before replacing parts.P25B2Fuel Level Sensor A or B StuckLow priorityFuel System30–120 minutes for initial diagnosisP25B2 relates to fuel level sensor a or b stuck. Check the fault conditions and vehicle-specific procedure before replacing parts.P25B3Turbocharger/Supercharger Wastegate A Stuck OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP25B3 relates to turbocharger/supercharger wastegate a stuck open. Check the fault conditions and vehicle-specific procedure before replacing parts.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.