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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

FiltersSeverity · family

Severity

All severities9253 Low priority305 Check soon8256 Urgent621

Code family

All families9253 P · Powertrain7353 B · Body193 C · Chassis479 U · Network1228

Vehicle coverage

These are generic OBD2 definitions. Exact make, model, engine, and year compatibility will appear after vehicle-fitment data is added.

Diagnostic codes

Showing 361–384 of 9253

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C0539Motor Control B Supply Voltage Circuit/OpenCheck soonChassis & Brakes45–120 minutes for initial diagnosisC0539 concerns motor control b supply voltage circuit/open. Learn what this fault indicates and where to begin diagnosis.C053AABS Valves Missing CalibrationCheck soonChassis & Brakes45–120 minutes for initial diagnosisC053A concerns abs valves missing calibration. Learn what this fault indicates and where to begin diagnosis.C053BABS Valves Supply Voltage Circuit/OpenCheck soonChassis & Brakes45–120 minutes for initial diagnosisC053B concerns abs valves supply voltage circuit/open. Learn what this fault indicates and where to begin diagnosis.C053CWheel Speed Sensor Generic Range/PerformanceCheck soonChassis & Brakes45–120 minutes for initial diagnosisC053C concerns wheel speed sensor generic range/performance. Learn what this fault indicates and where to begin diagnosis.C053DBrake Pressure Sensor A Range/PerformanceUrgentChassis & Brakes45–120 minutes for initial diagnosisC053D concerns brake pressure sensor a range/performance. Learn what this fault indicates and where to begin diagnosis.C053EBrake Pressure Sensor A Circuit LowUrgentChassis & Brakes45–120 minutes for initial diagnosisC053E concerns brake pressure sensor a circuit low. Learn what this fault indicates and where to begin diagnosis.C053FBrake Pressure Sensor A Circuit HighUrgentChassis & Brakes45–120 minutes for initial diagnosisC053F concerns brake pressure sensor a circuit high. Learn what this fault indicates and where to begin diagnosis.C0540Brake Pressure Sensor A Circuit/OpenUrgentChassis & Brakes45–120 minutes for initial diagnosisC0540 concerns brake pressure sensor a circuit/open. Learn what this fault indicates and where to begin diagnosis.C0541Brake Pressure Sensor B Range/PerformanceUrgentChassis & Brakes45–120 minutes for initial diagnosisC0541 concerns brake pressure sensor b range/performance. Learn what this fault indicates and where to begin diagnosis.C0542Brake Pressure Sensor B Circuit LowUrgentChassis & Brakes45–120 minutes for initial diagnosisC0542 concerns brake pressure sensor b circuit low. Learn what this fault indicates and where to begin diagnosis.C0543Brake Pressure Sensor B Circuit HighUrgentChassis & Brakes45–120 minutes for initial diagnosisC0543 concerns brake pressure sensor b circuit high. Learn what this fault indicates and where to begin diagnosis.C0544Brake Pressure Sensor B Circuit/OpenUrgentChassis & Brakes45–120 minutes for initial diagnosisC0544 concerns brake pressure sensor b circuit/open. Learn what this fault indicates and where to begin diagnosis.C0545VIN Not Programmed or Incompatible - BSCMCheck soonChassis & Brakes45–120 minutes for initial diagnosisC0545 concerns vin not programmed or incompatible - bscm. Learn what this fault indicates and where to begin diagnosis.C0546VIN Not Programmed or IncompatibleCheck soonChassis & Brakes45–120 minutes for initial diagnosisC0546 concerns vin not programmed or incompatible. Learn what this fault indicates and where to begin diagnosis.C0547Vacuum Sensor Supply Voltage Circuit/OpenCheck soonChassis & Brakes45–120 minutes for initial diagnosisC0547 concerns vacuum sensor supply voltage circuit/open. Learn what this fault indicates and where to begin diagnosis.C0548Vacuum Sensor Supply Voltage LowCheck soonChassis & Brakes45–120 minutes for initial diagnosisC0548 concerns vacuum sensor supply voltage low. Learn what this fault indicates and where to begin diagnosis.C0549Vacuum Sensor A Circuit/OpenCheck soonChassis & Brakes45–120 minutes for initial diagnosisC0549 concerns vacuum sensor a circuit/open. Learn what this fault indicates and where to begin diagnosis.C054AVacuum Sensor A Range/PerformanceCheck soonChassis & Brakes45–120 minutes for initial diagnosisC054A concerns vacuum sensor a range/performance. Learn what this fault indicates and where to begin diagnosis.C054BVacuum Sensor A Circuit LowCheck soonChassis & Brakes45–120 minutes for initial diagnosisC054B concerns vacuum sensor a circuit low. Learn what this fault indicates and where to begin diagnosis.C054CVacuum Sensor A Circuit HighCheck soonChassis & Brakes45–120 minutes for initial diagnosisC054C concerns vacuum sensor a circuit high. Learn what this fault indicates and where to begin diagnosis.C054DVacuum Sensor B Circuit/OpenCheck soonChassis & Brakes45–120 minutes for initial diagnosisC054D concerns vacuum sensor b circuit/open. Learn what this fault indicates and where to begin diagnosis.C054EVacuum Sensor B Range/PerformanceCheck soonChassis & Brakes45–120 minutes for initial diagnosisC054E concerns vacuum sensor b range/performance. Learn what this fault indicates and where to begin diagnosis.C054FVacuum Sensor B Circuit LowCheck soonChassis & Brakes45–120 minutes for initial diagnosisC054F concerns vacuum sensor b circuit low. Learn what this fault indicates and where to begin diagnosis.C0550Vacuum Sensor B Circuit HighCheck soonChassis & Brakes45–120 minutes for initial diagnosisC0550 concerns vacuum sensor b circuit high. Learn what this fault indicates and where to begin diagnosis.