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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 4777–4800 of 7353

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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.P24EANH3 Sensor Supply Voltage CircuitCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP24EA relates to nh3 sensor supply voltage circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P24EBNH3 Sensor Supply Voltage Circuit LowCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP24EB relates to nh3 sensor supply voltage circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P24ECNH3 Sensor Supply Voltage Circuit HighCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP24EC relates to nh3 sensor supply voltage circuit high. 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.P24F2EGR Temperature/Charge Air Cooler Temperature CorrelationCheck soonEmissions System30–120 minutes for initial diagnosisP24F2 relates to egr temperature/charge air cooler temperature correlation. Check the fault conditions and vehicle-specific procedure before replacing parts.P24F3Reductant Tank Temperature/Fuel Temperature CorrelationCheck soonFuel System30–120 minutes for initial diagnosisP24F3 relates to reductant tank temperature/fuel temperature correlation. 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.P24F6Exhaust Aftertreatment Fuel Air Purge Valve Stuck OpenCheck soonEmissions System30–120 minutes for initial diagnosisP24F6 relates to exhaust aftertreatment fuel air purge valve stuck open. Check the fault conditions and vehicle-specific procedure before replacing parts.P24F7Exhaust Aftertreatment Fuel Air Purge Valve Stuck ClosedCheck soonEmissions System30–120 minutes for initial diagnosisP24F7 relates to exhaust aftertreatment fuel air purge valve stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P24F8Exhaust Aftertreatment Fuel Air Purge Valve Control CircuitCheck soonEmissions System30–120 minutes for initial diagnosisP24F8 relates to exhaust aftertreatment fuel air purge valve control circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P24F9Exhaust Aftertreatment Fuel Air Purge Valve Control Circuit Range/PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP24F9 relates to exhaust aftertreatment fuel air purge valve control circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P24FAExhaust Aftertreatment Fuel Air Purge Valve Control Circuit LowCheck soonEmissions System30–120 minutes for initial diagnosisP24FA relates to exhaust aftertreatment fuel air purge valve control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P24FBExhaust Aftertreatment Fuel Air Purge Valve Control Circuit HighCheck soonEmissions System30–120 minutes for initial diagnosisP24FB relates to exhaust aftertreatment fuel air purge valve control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.