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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 1153–1176 of 8256

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P03FFIgnition L Control Signal Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP03FF relates to ignition l control signal circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0407Exhaust Gas Recirculation Sensor B Circuit LowCheck soonEmissions System30–90 minutes for initial diagnosisP0407 means the EGR position sensor B signal is below the expected electrical range. Learn what to check before replacing parts.P0408Exhaust Gas Recirculation Sensor B Circuit HighCheck soonEmissions System30–90 minutes for initial diagnosisP0408 means the EGR position sensor B signal is above the expected electrical range. Learn what to check before replacing parts.P0409Exhaust Gas Recirculation Sensor A CircuitCheck soonEmissions System30–90 minutes for initial diagnosisP0409 indicates the control module detected a fault in the EGR position-sensor A circuit. Learn what to inspect before replacing parts.P040AEGR Temperature Sensor A CircuitCheck soonEmissions System30–120 minutes for initial diagnosisP040A relates to egr temperature sensor a circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P040BEGR Temperature Sensor A Circuit Range/PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP040B relates to egr temperature sensor a circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P040CEGR Temperature Sensor A Circuit LowCheck soonEmissions System30–120 minutes for initial diagnosisP040C relates to egr temperature sensor a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P040DEGR Temperature Sensor A Circuit HighCheck soonEmissions System30–120 minutes for initial diagnosisP040D relates to egr temperature sensor a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P040EEGR Temperature Sensor A Circuit Intermittent/ErraticCheck soonEmissions System30–120 minutes for initial diagnosisP040E relates to egr temperature sensor a circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P040FEGR Temperature Sensor A/B CorrelationCheck soonEmissions System30–120 minutes for initial diagnosisP040F relates to egr temperature sensor a/b correlation. Check the fault conditions and vehicle-specific procedure before replacing parts.P0415AIR System Switching Valve B CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0415 relates to air system switching valve b circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P0416AIR System Switching Valve B Circuit OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0416 relates to air system switching valve b circuit open. Check the fault conditions and vehicle-specific procedure before replacing parts.P0417AIR System Switching Valve B Circuit ShortedCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0417 relates to air system switching valve b circuit shorted. Check the fault conditions and vehicle-specific procedure before replacing parts.P0418AIR System Control A CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0418 relates to air system control a circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P0419AIR System Control B CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0419 relates to air system control b circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P041AEGR Temperature Sensor B CircuitCheck soonEmissions System30–120 minutes for initial diagnosisP041A relates to egr temperature sensor b circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P041BEGR Temperature Sensor B Circuit Range/PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP041B relates to egr temperature sensor b circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P041CEGR Temperature Sensor B Circuit LowCheck soonEmissions System30–120 minutes for initial diagnosisP041C relates to egr temperature sensor b circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P041DEGR Temperature Sensor B Circuit HighCheck soonEmissions System30–120 minutes for initial diagnosisP041D relates to egr temperature sensor b circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P041EEGR Temperature Sensor B Circuit Intermittent/ErraticCheck soonEmissions System30–120 minutes for initial diagnosisP041E relates to egr temperature sensor b circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P041FAIR System Switching Valve A Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP041F relates to air system switching valve a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0424Heated Catalyst Temperature Below Threshold (Bank 1)Check soonEmissions System30–90 minutes for initial diagnosisP0424 indicates the monitored heated-catalyst temperature on Bank 1 is below the expected threshold. Learn what to inspect before replacing parts.P0425Catalyst Temperature Sensor Circuit (Bank 1, Sensor 1)Check soonEmissions System30–90 minutes for initial diagnosisP0425 indicates the control module detected a fault in the Bank 1 Sensor 1 catalyst-temperature-sensor circuit. Learn what to inspect before replacing parts.P0426Catalyst Temperature Sensor Circuit Range/Performance (Bank 1, Sensor 1)Check soonEmissions System30–90 minutes for initial diagnosisP0426 indicates the Bank 1 Sensor 1 catalyst-temperature signal is outside its expected range or does not respond plausibly. Learn what to inspect before replacing parts.