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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.

Low priority P · Powertrain Clear all

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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 298

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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.P0531A/C Refrigerant Pressure Sensor Range/PerformanceLow prioritySensors & Electronics30–120 minutes for initial diagnosisP0531 indicates a fault related to a/c refrigerant pressure sensor range/performance. Learn the likely causes and a practical diagnostic order before replacing parts.P0532A/C Refrigerant Pressure Sensor Circuit LowLow prioritySensors & Electronics30–120 minutes for initial diagnosisP0532 indicates a fault related to a/c refrigerant pressure sensor circuit low. Learn the likely causes and a practical diagnostic order before replacing parts.P0533A/C Refrigerant Pressure Sensor Circuit HighLow prioritySensors & Electronics30–120 minutes for initial diagnosisP0533 indicates a fault related to a/c refrigerant pressure sensor circuit high. Learn the likely causes and a practical diagnostic order before replacing parts.P0534Air Conditioner Refrigerant Charge LossLow prioritySensors & Electronics30–120 minutes for initial diagnosisP0534 indicates a fault related to air conditioner refrigerant charge loss. Learn the likely causes and a practical diagnostic order before replacing parts.P0535A/C Evaporator Temperature Sensor CircuitLow priorityEmissions System30–120 minutes for initial diagnosisP0535 relates to a/c evaporator temperature sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P0536A/C Evaporator Temperature Sensor Circuit Range/PerformanceLow priorityEmissions System30–120 minutes for initial diagnosisP0536 relates to a/c evaporator temperature sensor circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0537A/C Evaporator Temperature Sensor Circuit LowLow priorityEmissions System30–120 minutes for initial diagnosisP0537 relates to a/c evaporator temperature sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.