Diagnostic library

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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 8209–8232 of 9253

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U02A2Lost Communication With Reductant Quality ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02A2 concerns lost communication with reductant quality module. Learn what this fault indicates and where to begin diagnosis.U02A3Lost Communication With Particulate Matter SensorCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02A3 concerns lost communication with particulate matter sensor. Learn what this fault indicates and where to begin diagnosis.U02A4Lost Communication With NH3 SensorCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02A4 concerns lost communication with nh3 sensor. Learn what this fault indicates and where to begin diagnosis.U02A5Lost Communication With Reductant Heater Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02A5 concerns lost communication with reductant heater control module. Learn what this fault indicates and where to begin diagnosis.U02A6Lost Communication With Safety Integration Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02A6 concerns lost communication with safety integration control module. Learn what this fault indicates and where to begin diagnosis.U02A7Lost Communication With Engine Sound Control 1Check soonNetwork & Communication45–120 minutes for initial diagnosisU02A7 concerns lost communication with engine sound control 1. Learn what this fault indicates and where to begin diagnosis.U02A8Lost Communication With Engine Sound Control 2Check soonNetwork & Communication45–120 minutes for initial diagnosisU02A8 concerns lost communication with engine sound control 2. Learn what this fault indicates and where to begin diagnosis.U02A9Lost Communication With Charge Air Cooler Coolant Pump ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU02A9 concerns lost communication with charge air cooler coolant pump a. Learn what this fault indicates and where to begin diagnosis.U02AALost Communication With Engine Disconnect ClutchCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02AA concerns lost communication with engine disconnect clutch. Learn what this fault indicates and where to begin diagnosis.U02ABLost Communication With Vehicle Thermal Management Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02AB concerns lost communication with vehicle thermal management control module. Learn what this fault indicates and where to begin diagnosis.U02ACLost Communication With Turbocharger/Supercharger Boost Control ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU02AC concerns lost communication with turbocharger/supercharger boost control a. Learn what this fault indicates and where to begin diagnosis.U02ADLost Communication With Turbocharger/Supercharger Boost Control BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02AD concerns lost communication with turbocharger/supercharger boost control b. Learn what this fault indicates and where to begin diagnosis.U02AELost Communications With Hybrid/EV Battery Coolant PumpCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02AE concerns lost communications with hybrid/ev battery coolant pump. Learn what this fault indicates and where to begin diagnosis.U02AFLost Communication With Turbocharger Turbine Inlet Valve Position SensorCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02AF concerns lost communication with turbocharger turbine inlet valve position sensor. Learn what this fault indicates and where to begin diagnosis.U02B0Lost Communication With Turbocharger/Supercharger Boost Control B Position SensorCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02B0 concerns lost communication with turbocharger/supercharger boost control b position sensor. Learn what this fault indicates and where to begin diagnosis.U02B1Lost Communication With Comfort and Convenience Display ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU02B1 concerns lost communication with comfort and convenience display a. Learn what this fault indicates and where to begin diagnosis.U02B2Lost Communication With Comfort and Convenience Display BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02B2 concerns lost communication with comfort and convenience display b. Learn what this fault indicates and where to begin diagnosis.U02B3Lost Communication With Driver Monitoring System ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02B3 concerns lost communication with driver monitoring system module. Learn what this fault indicates and where to begin diagnosis.U02B4Lost Communication With Front Radar Module ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU02B4 concerns lost communication with front radar module a. Learn what this fault indicates and where to begin diagnosis.U02B5Lost Communication With Front Radar Module BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02B5 concerns lost communication with front radar module b. Learn what this fault indicates and where to begin diagnosis.U02B6Lost Communication With Rear Radar Module ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU02B6 concerns lost communication with rear radar module a. Learn what this fault indicates and where to begin diagnosis.U02B7Lost Communication With Rear Radar Module BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02B7 concerns lost communication with rear radar module b. Learn what this fault indicates and where to begin diagnosis.U02B8Lost Communication With Rear Radar Module CCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02B8 concerns lost communication with rear radar module c. Learn what this fault indicates and where to begin diagnosis.U02B9Lost Communication With Rear Radar Module DCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02B9 concerns lost communication with rear radar module d. Learn what this fault indicates and where to begin diagnosis.