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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.

Urgent P · Powertrain Clear all

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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 241–264 of 302

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P20EDSCR NOx Pre-Catalyst - Over Temperature Bank 1UrgentEmissions System30–120 minutes for initial diagnosisP20ED relates to scr nox pre-catalyst - over temperature bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P20F0SCR NOx Catalyst - Over Temperature Bank 2UrgentEmissions System30–120 minutes for initial diagnosisP20F0 relates to scr nox catalyst - over temperature bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P20F1SCR NOx Pre-Catalyst - Over Temperature Bank 2UrgentEmissions System30–120 minutes for initial diagnosisP20F1 relates to scr nox pre-catalyst - over temperature bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P21B4NOx Adsorber - Over Temperature Bank 1UrgentSensors & Electronics30–120 minutes for initial diagnosisP21B4 relates to nox adsorber - over temperature bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P21B5NOx Adsorber - Over Temperature Bank 2UrgentSensors & Electronics30–120 minutes for initial diagnosisP21B5 relates to nox adsorber - over temperature bank 2. 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.P263EGlow Plug Control Module 1 Over TemperatureUrgentSensors & Electronics30–120 minutes for initial diagnosisP263E relates to glow plug control module 1 over temperature. Check the fault conditions and vehicle-specific procedure before replacing parts.P263FGlow Plug Control Module 2 Over TemperatureUrgentSensors & Electronics30–120 minutes for initial diagnosisP263F relates to glow plug control module 2 over temperature. Check the fault conditions and vehicle-specific procedure before replacing parts.P26CEEngine Coolant Pump Overspeed/Air In SystemUrgentEngine Problems30–120 minutes for initial diagnosisP26CE relates to engine coolant pump overspeed/air in system. Check the fault conditions and vehicle-specific procedure before replacing parts.P26D2Engine Coolant Pump Control Module Over TemperatureUrgentEngine Problems30–120 minutes for initial diagnosisP26D2 relates to engine coolant pump control module over temperature. Check the fault conditions and vehicle-specific procedure before replacing parts.P26FACoolant Pump C Overspeed/Air in SystemUrgentEngine Problems30–120 minutes for initial diagnosisP26FA relates to coolant pump c overspeed/air in system. Check the fault conditions and vehicle-specific procedure before replacing parts.P273EGear Shift Control Module A Over TemperatureUrgentTransmission Issues30–120 minutes for initial diagnosisP273E relates to gear shift control module a over temperature. Check the fault conditions and vehicle-specific procedure before replacing parts.P273FTransmission Fluid Temperature Sensor B Over Temperature ConditionUrgentTransmission Issues30–120 minutes for initial diagnosisP273F relates to transmission fluid temperature sensor b over temperature condition. Check the fault conditions and vehicle-specific procedure before replacing parts.P274FTransmission Fluid Temperature Sensor C Over Temperature ConditionUrgentTransmission Issues30–120 minutes for initial diagnosisP274F relates to transmission fluid temperature sensor c over temperature condition. Check the fault conditions and vehicle-specific procedure before replacing parts.P275FTransmission Fluid Temperature Sensor D Over Temperature ConditionUrgentTransmission Issues30–120 minutes for initial diagnosisP275F relates to transmission fluid temperature sensor d over temperature condition. Check the fault conditions and vehicle-specific procedure before replacing parts.P277DElectric/Auxiliary Transmission Fluid Pump B Motor Over TemperatureUrgentTransmission Issues30–120 minutes for initial diagnosisP277D relates to electric/auxiliary transmission fluid pump b motor over temperature. Check the fault conditions and vehicle-specific procedure before replacing parts.P28C9Clutch A Motor OverspeedUrgentTransmission Issues30–120 minutes for initial diagnosisP28C9 relates to clutch a motor overspeed. Check the fault conditions and vehicle-specific procedure before replacing parts.P28D8Clutch B Motor OverspeedUrgentTransmission Issues30–120 minutes for initial diagnosisP28D8 relates to clutch b motor overspeed. Check the fault conditions and vehicle-specific procedure before replacing parts.P28E6Shift Motor OverspeedUrgentTransmission Issues30–120 minutes for initial diagnosisP28E6 relates to shift motor overspeed. Check the fault conditions and vehicle-specific procedure before replacing parts.P28EDElectric/Auxiliary Transmission Fluid Pump B OverspeedUrgentTransmission Issues30–120 minutes for initial diagnosisP28ED relates to electric/auxiliary transmission fluid pump b overspeed. Check the fault conditions and vehicle-specific procedure before replacing parts.P2B29Hybrid/EV Battery Pack Coolant Pump A Overspeed - Dry RunUrgentElectrical & Charging System30–120 minutes for initial diagnosisP2B29 relates to hybrid/ev battery pack coolant pump a overspeed - dry run. Check the fault conditions and vehicle-specific procedure before replacing parts.P2B2AHybrid/EV Electronics Coolant Pump A Overspeed - Dry RunUrgentEngine Problems30–120 minutes for initial diagnosisP2B2A relates to hybrid/ev electronics coolant pump a overspeed - dry run. Check the fault conditions and vehicle-specific procedure before replacing parts.P2B65Coolant Pump B Overspeed/Air in SystemUrgentEngine Problems30–120 minutes for initial diagnosisP2B65 relates to coolant pump b overspeed/air in system. Check the fault conditions and vehicle-specific procedure before replacing parts.P2B6CCoolant Pump D Overspeed/Air in SystemUrgentEngine Problems30–120 minutes for initial diagnosisP2B6C relates to coolant pump d overspeed/air in system. Check the fault conditions and vehicle-specific procedure before replacing parts.