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9,253 diagnostic guides

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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 73–96 of 378

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P04D0EGR Temperature Sensor C Circuit LowCheck soonEmissions SystemP04D1EGR Temperature Sensor C Circuit HighCheck soonEmissions SystemP04D2EGR Temperature Sensor C Circuit Intermittent/ErraticCheck soonEmissions SystemP04D8Excessive Time To Enter Closed Loop EGR ControlCheck soonEmissions SystemP04D9Closed Loop EGR Control At Limit - Flow Too LowCheck soonEmissions SystemP04DAClosed Loop EGR Control At Limit - Flow Too HighCheck soonEmissions SystemP04DDCold Start EGR A Flow Insufficient DetectedCheck soonEmissions SystemP04DECold Start EGR A Flow Excessive DetectedCheck soonEmissions SystemP04E5EGR Temperature Sensor D CircuitCheck soonEmissions SystemP04E6EGR Temperature Sensor D Circuit Range/PerformanceCheck soonEmissions SystemP04E7EGR Temperature Sensor D Circuit LowCheck soonEmissions SystemP04E8EGR Temperature Sensor D Circuit HighCheck soonEmissions SystemP04E9EGR Temperature Sensor D Circuit Intermittent/ErraticCheck soonEmissions SystemP04F2Catalyst Heater Supply Voltage Bank 1Check soonEmissions SystemP04F3Catalyst Heater Supply Voltage Bank 2Check soonEmissions SystemP04F4Catalyst Heater Circuit Low Bank 1Check soonEmissions SystemP04F5Catalyst Heater Circuit Low Bank 2Check soonEmissions SystemP04F6Catalyst Heater Circuit High Bank 1Check soonEmissions SystemP04F7Catalyst Heater Circuit High Bank 2Check soonEmissions SystemP04F8Catalyst Heater Circuit Intermittent Bank 1Check soonEmissions SystemP04F9Catalyst Heater Circuit Intermittent Bank 2Check soonEmissions SystemP04FAEGR A Control Temperature Too HighCheck soonEmissions SystemP04FDEGR Actuator A Control Processor PerformanceCheck soonEmissions SystemP04FECatalyst Heater Circuit Performance Bank 1Check soonEmissions System