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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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Severity

All severities9253 Low priority305 Check soon8256 Urgent621

Code family

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 1249–1272 of 1939

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P24CBReductant Tank Cap Switch CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP24CB relates to reductant tank cap switch circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P24CCReductant Tank Cap Switch Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP24CC relates to reductant tank cap switch circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P24CDReductant Tank Cap Switch Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP24CD relates to reductant tank cap switch circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P24CEReductant Tank Cap Switch Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP24CE relates to reductant tank cap switch circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P24CFReductant Tank Cap Switch Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP24CF relates to reductant tank cap switch circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P24D2Reductant Heater A Sense CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP24D2 relates to reductant heater a sense circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P24D3Reductant Heater B Sense CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP24D3 relates to reductant heater b sense circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P24E1NH3 Sensor CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP24E1 relates to nh3 sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P24E2NH3 Sensor Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP24E2 relates to nh3 sensor circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P24E3NH3 Sensor Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP24E3 relates to nh3 sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P24E4NH3 Sensor Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP24E4 relates to nh3 sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P24E5NH3 Sensor Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP24E5 relates to nh3 sensor circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P24E6NH3 Sensor Heater Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP24E6 relates to nh3 sensor heater circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P24E7NH3 Sensor Heater Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP24E7 relates to nh3 sensor heater circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P24E8NH3 Sensor Heater Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP24E8 relates to nh3 sensor heater circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P24E9NH3 Sensor Heater Circuit PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP24E9 relates to nh3 sensor heater circuit performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P24EDNH3 Sensor Calibration MemoryCheck soonSensors & Electronics30–120 minutes for initial diagnosisP24ED relates to nh3 sensor calibration memory. Check the fault conditions and vehicle-specific procedure before replacing parts.P24EENH3 Sensor Processor PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP24EE relates to nh3 sensor processor performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P24EFControl Module Wake-up Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP24EF relates to control module wake-up circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P24F0Control Module Wake-up Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP24F0 relates to control module wake-up circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P24F1Control Module Wake-up Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP24F1 relates to control module wake-up circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P24F4NOx Sensor Delayed Response - High to Low Bank 1 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP24F4 relates to nox sensor delayed response - high to low bank 1 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P24F5NOx Sensor Delayed Response - High to Low Bank 1 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP24F5 relates to nox sensor delayed response - high to low bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P24FFReductant Temperature Too HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP24FF relates to reductant temperature too high. Check the fault conditions and vehicle-specific procedure before replacing parts.