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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 73–96 of 305

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P04ADEVAP System Purge Control Valve B Circuit HighLow priorityEmissions System30–120 minutes for initial diagnosisP04AD relates to evap system purge control valve b circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P04AEEVAP System Purge Control Valve B Performance/Stuck OpenLow priorityEmissions System30–120 minutes for initial diagnosisP04AE relates to evap system purge control valve b performance/stuck open. Check the fault conditions and vehicle-specific procedure before replacing parts.P04AFEVAP System Purge Control Valve B Stuck ClosedLow priorityEmissions System30–120 minutes for initial diagnosisP04AF relates to evap system purge control valve b stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P04BBFuel Fill Door Lock Control Circuit/OpenLow priorityFuel System30–120 minutes for initial diagnosisP04BB relates to fuel fill door lock control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P04BCFuel Fill Door Lock Control Range/PerformanceLow priorityFuel System30–120 minutes for initial diagnosisP04BC relates to fuel fill door lock control range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P04BDFuel Fill Door Lock Control Circuit LowLow priorityFuel System30–120 minutes for initial diagnosisP04BD relates to fuel fill door lock control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P04BEFuel Fill Door Lock Control Circuit HighLow priorityFuel System30–120 minutes for initial diagnosisP04BE relates to fuel fill door lock control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P04C3Fuel Fill Door Lock Position Sensor/Switch CircuitLow priorityFuel System30–120 minutes for initial diagnosisP04C3 relates to fuel fill door lock position sensor/switch circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P04C4Fuel Fill Door Lock Position Sensor/Switch Circuit Range/PerformanceLow priorityFuel System30–120 minutes for initial diagnosisP04C4 relates to fuel fill door lock position sensor/switch circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P04C5Fuel Fill Door Lock Position Sensor/Switch Circuit LowLow priorityFuel System30–120 minutes for initial diagnosisP04C5 relates to fuel fill door lock position sensor/switch circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P04C6Fuel Fill Door Lock Position Sensor/Switch Circuit HighLow priorityFuel System30–120 minutes for initial diagnosisP04C6 relates to fuel fill door lock position sensor/switch circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P04C7Fuel Fill Door Lock Position Sensor/Switch Circuit Intermittent/ErraticLow priorityFuel System30–120 minutes for initial diagnosisP04C7 relates to fuel fill door lock position sensor/switch circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P04DFEVAP System Purge Control Valve A Performance/Stuck OpenLow priorityEmissions System30–120 minutes for initial diagnosisP04DF relates to evap system purge control valve a performance/stuck open. Check the fault conditions and vehicle-specific procedure before replacing parts.P04E0EVAP System Purge Control Valve A Stuck ClosedLow priorityEmissions System30–120 minutes for initial diagnosisP04E0 relates to evap system purge control valve a stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P04EAEVAP System Small Leak Detected - Fuel Tank SideLow priorityEmissions System30–120 minutes for initial diagnosisP04EA relates to evap system small leak detected - fuel tank side. Check the fault conditions and vehicle-specific procedure before replacing parts.P04EBEVAP System Small Leak Detected - Fresh Air SideLow priorityEmissions System30–120 minutes for initial diagnosisP04EB relates to evap system small leak detected - fresh air side. Check the fault conditions and vehicle-specific procedure before replacing parts.P04ECEVAP System Large Leak Detected - Fuel Tank SideLow priorityEmissions System30–120 minutes for initial diagnosisP04EC relates to evap system large leak detected - fuel tank side. Check the fault conditions and vehicle-specific procedure before replacing parts.P04EDEVAP System Large Leak Detected - Fresh Air SideLow priorityEmissions System30–120 minutes for initial diagnosisP04ED relates to evap system large leak detected - fresh air side. Check the fault conditions and vehicle-specific procedure before replacing parts.P04EEEVAP System Very Small Leak Detected - Fuel Tank SideLow priorityEmissions System30–120 minutes for initial diagnosisP04EE relates to evap system very small leak detected - fuel tank side. Check the fault conditions and vehicle-specific procedure before replacing parts.P04EFEVAP System Very Small Leak Detected - Fresh Air SideLow priorityEmissions System30–120 minutes for initial diagnosisP04EF relates to evap system very small leak detected - fresh air side. Check the fault conditions and vehicle-specific procedure before replacing parts.P04F0EVAP System High Load Purge Line A PerformanceLow priorityEmissions System30–120 minutes for initial diagnosisP04F0 relates to evap system high load purge line a performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P04F1EVAP System Purge Line PerformanceLow priorityEmissions System30–120 minutes for initial diagnosisP04F1 relates to evap system purge line performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0525Cruise Control Servo Control Circuit Range/PerformanceLow prioritySensors & Electronics30–120 minutes for initial diagnosisP0525 relates to cruise control servo control circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0530A/C Refrigerant Pressure Sensor CircuitLow prioritySensors & Electronics30–120 minutes for initial diagnosisP0530 indicates a fault related to a/c refrigerant pressure sensor circuit. Learn the likely causes and a practical diagnostic order before replacing parts.