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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 289–312 of 1939

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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.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.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.P044FAIR System Switching Valve A Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP044F relates to air system switching valve a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0475Exhaust Pressure Control Valve ACheck soonSensors & Electronics30–120 minutes for initial diagnosisP0475 relates to exhaust pressure control valve a. Check the fault conditions and vehicle-specific procedure before replacing parts.P0476Exhaust Pressure Control Valve A Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0476 relates to exhaust pressure control valve a range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0477Exhaust Pressure Control Valve A LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0477 relates to exhaust pressure control valve a low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0478Exhaust Pressure Control Valve A HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0478 relates to exhaust pressure control valve a high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0479Exhaust Pressure Control Valve A IntermittentCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0479 relates to exhaust pressure control valve a intermittent. Check the fault conditions and vehicle-specific procedure before replacing parts.P047AExhaust Pressure Sensor B CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP047A relates to exhaust pressure sensor b circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P047BExhaust Pressure Sensor B Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP047B relates to exhaust pressure sensor b circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P047CExhaust Pressure Sensor B Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP047C relates to exhaust pressure sensor b circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P047DExhaust Pressure Sensor B Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP047D relates to exhaust pressure sensor b circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P047EExhaust Pressure Sensor B Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP047E relates to exhaust pressure sensor b circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P047FExhaust Pressure Control Valve A Stuck OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP047F relates to exhaust pressure control valve a stuck open. Check the fault conditions and vehicle-specific procedure before replacing parts.P048AExhaust Pressure Control Valve A Stuck ClosedCheck soonSensors & Electronics30–120 minutes for initial diagnosisP048A relates to exhaust pressure control valve a stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P048BExhaust Pressure Control Valve A Position Sensor/Switch CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP048B relates to exhaust pressure control valve a position sensor/switch circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P048CExhaust Pressure Control Valve A Position Sensor/Switch Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP048C relates to exhaust pressure control valve a position sensor/switch circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P048DExhaust Pressure Control Valve A Position Sensor/Switch Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP048D relates to exhaust pressure control valve a position sensor/switch circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P048EExhaust Pressure Control Valve A Position Sensor/Switch Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP048E relates to exhaust pressure control valve a position sensor/switch circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.