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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

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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 8256

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C0035Left Front Wheel Speed SensorCheck soonChassis & Brakes45–120 minutes for initial diagnosisC0035 means Left Front Wheel Speed Sensor. Review likely symptoms, causes, safety considerations, and a sensible diagnostic order.C0040Right Front Wheel Speed SensorCheck soonChassis & Brakes45–120 minutes for initial diagnosisC0040 means Right Front Wheel Speed Sensor. Review likely symptoms, causes, safety considerations, and a sensible diagnostic order.C0045Left Rear Wheel Speed SensorCheck soonChassis & Brakes45–120 minutes for initial diagnosisC0045 means Left Rear Wheel Speed Sensor. Review likely symptoms, causes, safety considerations, and a sensible diagnostic order.C0050Right Rear Wheel Speed SensorCheck soonChassis & Brakes45–120 minutes for initial diagnosisC0050 means Right Rear Wheel Speed Sensor. Review likely symptoms, causes, safety considerations, and a sensible diagnostic order.P0069Manifold Absolute Pressure–Barometric Pressure CorrelationCheck soonSensors & Electronics45–120 minutes for initial diagnosisP0069 means Manifold Absolute Pressure–Barometric Pressure Correlation. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.P0089Fuel Pressure Regulator 1 PerformanceCheck soonFuel System45–120 minutes for initial diagnosisP0089 means Fuel Pressure Regulator 1 Performance. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.P0128Coolant Thermostat Below Regulating TemperatureCheck soonEngine Problems30–75 minutesDiagnose P0128 thermostat code. Learn why your engine isn't reaching operating temperature.P0171System Too Lean Bank 1 - Complete GuideCheck soonFuel System45–120 minutesDiagnose and fix P0171 system too lean code. Understand what causes a lean fuel mixture and how to solve it with our comprehensive guide.P0221Throttle/Pedal Position Sensor/Switch B Circuit Range/PerformanceCheck soonSensors & Electronics45–120 minutes for initial diagnosisP0221 means Throttle/Pedal Position Sensor/Switch B Circuit Range/Performance. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.P0235Turbocharger/Supercharger Boost Sensor A CircuitCheck soonSensors & Electronics45–120 minutes for initial diagnosisP0235 means Turbocharger/Supercharger Boost Sensor A Circuit. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.P0756Shift Solenoid B Performance or Stuck OffCheck soonTransmission Issues45–120 minutes for initial diagnosisP0756 means Shift Solenoid B Performance or Stuck Off. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.P0760Shift Solenoid C MalfunctionCheck soonTransmission Issues45–120 minutes for initial diagnosisP0760 means Shift Solenoid C Malfunction. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.U0001High Speed CAN Communication BusCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0001 means High Speed CAN Communication Bus. Review likely symptoms, causes, safety considerations, and a sensible diagnostic order.U0140Lost Communication With Body Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0140 means Lost Communication With Body Control Module. Review likely symptoms, causes, safety considerations, and a sensible diagnostic order.B0050Driver Seat Belt SensorCheck soonBody & Restraints45–120 minutes for initial diagnosisB0050 concerns driver seat belt sensor. Learn what this fault indicates and where to begin diagnosis.B0052Passenger Seat Belt SensorCheck soonBody & Restraints45–120 minutes for initial diagnosisB0052 concerns passenger seat belt sensor. Learn what this fault indicates and where to begin diagnosis.B0053Second Row Left Seat Belt SensorCheck soonBody & Restraints45–120 minutes for initial diagnosisB0053 concerns second row left seat belt sensor. Learn what this fault indicates and where to begin diagnosis.B0054Second Row Center Seat Belt SensorCheck soonBody & Restraints45–120 minutes for initial diagnosisB0054 concerns second row center seat belt sensor. Learn what this fault indicates and where to begin diagnosis.B0055Second Row Right Seat Belt SensorCheck soonBody & Restraints45–120 minutes for initial diagnosisB0055 concerns second row right seat belt sensor. Learn what this fault indicates and where to begin diagnosis.B0056Third Row Left Seat Belt SensorCheck soonBody & Restraints45–120 minutes for initial diagnosisB0056 concerns third row left seat belt sensor. Learn what this fault indicates and where to begin diagnosis.B0057Third Row Center Seat Belt SensorCheck soonBody & Restraints45–120 minutes for initial diagnosisB0057 concerns third row center seat belt sensor. Learn what this fault indicates and where to begin diagnosis.B0058Third Row Right Seat Belt SensorCheck soonBody & Restraints45–120 minutes for initial diagnosisB0058 concerns third row right seat belt sensor. Learn what this fault indicates and where to begin diagnosis.B0060Driver Seat Belt Tension SensorCheck soonBody & Restraints45–120 minutes for initial diagnosisB0060 concerns driver seat belt tension sensor. Learn what this fault indicates and where to begin diagnosis.B0061Passenger Seat Belt Tension SensorCheck soonBody & Restraints45–120 minutes for initial diagnosisB0061 concerns passenger seat belt tension sensor. Learn what this fault indicates and where to begin diagnosis.