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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.

Urgent C · Chassis Clear all

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Engine1049 Emissions515 Fuel1016 Sensors & Electronics2110 Transmission866 Electrical & Charging1797 Body & Restraints193 Chassis & Brakes479 Network & Communication1228

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Severity

All severities9253 Low priority305 Check soon8256 Urgent621

Code family

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 1–24 of 212

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C0021Brake Booster PerformanceUrgentChassis & Brakes45–120 minutes for initial diagnosisC0021 concerns brake booster performance. Learn what this fault indicates and where to begin diagnosis.C0022Brake Booster SolenoidUrgentChassis & Brakes45–120 minutes for initial diagnosisC0022 concerns brake booster solenoid. Learn what this fault indicates and where to begin diagnosis.C0024Brake Pedal Feedback Pressure Solenoid CircuitUrgentChassis & Brakes45–120 minutes for initial diagnosisC0024 concerns brake pedal feedback pressure solenoid circuit. Learn what this fault indicates and where to begin diagnosis.C0025Brake Pedal Feedback Pressure Sensor CircuitUrgentChassis & Brakes45–120 minutes for initial diagnosisC0025 concerns brake pedal feedback pressure sensor circuit. Learn what this fault indicates and where to begin diagnosis.C0041Brake Pedal Switch BUrgentChassis & Brakes45–120 minutes for initial diagnosisC0041 concerns brake pedal switch b. Learn what this fault indicates and where to begin diagnosis.C0042Brake Pedal Position Sensor Circuit AUrgentChassis & Brakes45–120 minutes for initial diagnosisC0042 concerns brake pedal position sensor circuit a. Learn what this fault indicates and where to begin diagnosis.C0043Brake Pedal Position Sensor Circuit BUrgentChassis & Brakes45–120 minutes for initial diagnosisC0043 concerns brake pedal position sensor circuit b. Learn what this fault indicates and where to begin diagnosis.C0044Brake Pressure Sensor AUrgentChassis & Brakes45–120 minutes for initial diagnosisC0044 concerns brake pressure sensor a. Learn what this fault indicates and where to begin diagnosis.C0046Brake Pressure Sensor A/BUrgentChassis & Brakes45–120 minutes for initial diagnosisC0046 concerns brake pressure sensor a/b. Learn what this fault indicates and where to begin diagnosis.C0047Brake Booster Pressure SensorUrgentChassis & Brakes45–120 minutes for initial diagnosisC0047 concerns brake booster pressure sensor. Learn what this fault indicates and where to begin diagnosis.C0048Brake Booster Travel SensorUrgentChassis & Brakes45–120 minutes for initial diagnosisC0048 concerns brake booster travel sensor. Learn what this fault indicates and where to begin diagnosis.C0049Brake Fluid LevelUrgentChassis & Brakes45–120 minutes for initial diagnosisC0049 concerns brake fluid level. Learn what this fault indicates and where to begin diagnosis.C004ABrake Lining Wear SensorUrgentChassis & Brakes45–120 minutes for initial diagnosisC004A concerns brake lining wear sensor. Learn what this fault indicates and where to begin diagnosis.C004BBrake Fluid Level Sensor/Switch Circuit/OpenUrgentChassis & Brakes45–120 minutes for initial diagnosisC004B concerns brake fluid level sensor/switch circuit/open. Learn what this fault indicates and where to begin diagnosis.C004CBrake Booster Motor A Position Sensor Exceeded Learning LimitUrgentChassis & Brakes45–120 minutes for initial diagnosisC004C concerns brake booster motor a position sensor exceeded learning limit. Learn what this fault indicates and where to begin diagnosis.C004DBrake System Pressure Slow ResponseUrgentChassis & Brakes45–120 minutes for initial diagnosisC004D concerns brake system pressure slow response. Learn what this fault indicates and where to begin diagnosis.C004EBrake System Pressure Control Valve Actuator StuckUrgentChassis & Brakes45–120 minutes for initial diagnosisC004E concerns brake system pressure control valve actuator stuck. Learn what this fault indicates and where to begin diagnosis.C0055Steering Wheel Position Sensor Signal DUrgentChassis & Brakes45–120 minutes for initial diagnosisC0055 concerns steering wheel position sensor signal d. Learn what this fault indicates and where to begin diagnosis.C0079Variable Effort SteeringUrgentChassis & Brakes45–120 minutes for initial diagnosisC0079 concerns variable effort steering. Learn what this fault indicates and where to begin diagnosis.C0082Brake System Malfunction IndicatorUrgentChassis & Brakes45–120 minutes for initial diagnosisC0082 concerns brake system malfunction indicator. Learn what this fault indicates and where to begin diagnosis.C0526Steering Angle Sensor ModuleUrgentChassis & Brakes45–120 minutes for initial diagnosisC0526 concerns steering angle sensor module. Learn what this fault indicates and where to begin diagnosis.C0527Steering Angle Sensor Module MechanicalUrgentChassis & Brakes45–120 minutes for initial diagnosisC0527 concerns steering angle sensor module mechanical. Learn what this fault indicates and where to begin diagnosis.C0528Steering Angle Sensor Module Range/PerformanceUrgentChassis & Brakes45–120 minutes for initial diagnosisC0528 concerns steering angle sensor module range/performance. Learn what this fault indicates and where to begin diagnosis.C0529Steering Angle Sensor Module Missing CalibrationUrgentChassis & Brakes45–120 minutes for initial diagnosisC0529 concerns steering angle sensor module missing calibration. Learn what this fault indicates and where to begin diagnosis.