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9,253 diagnostic guides
Find codes by symptomChoose what you notice to search matching code guides.
Rough idle or shakingVibration while stoppedHard to startLong cranking or no-startEngine stallsCuts out at idle or on the roadHesitates or loses powerSlow response when acceleratingBattery light is onCharging system warningHarsh 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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These are generic OBD2 definitions. Exact make, model, engine, and year compatibility will appear after vehicle-fitment data is added.
Diagnostic codes
Showing 505–528 of 1223
U0406Invalid Data Received From Fuel Injector Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0407Invalid Data Received From Glow Plug Control Module 1Check soonNetwork & Communication45–120 minutes for initial diagnosisU0408Invalid Data Received From Throttle Actuator A Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0409Invalid Data Received From Alternative Fuel Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU040AInvalid Data Received From Air Conditioning Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU040BInvalid Data Received From Exhaust Gas Recirculation Control Module ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU040CInvalid Data Received From Exhaust Gas Recirculation Control Module BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU040DInvalid Data Received From Turbocharger/Supercharger Control Module ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU040EInvalid Data Received From Turbocharger/Supercharger Control Module BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU040FInvalid Data Received From Reductant Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0410Invalid Data Received From Fuel Pump Control Module ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0411Invalid Data Received From Drive Motor Control Module ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0412Invalid Data Received From Battery Energy Control Module ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0413Invalid Data Received From Battery Energy Control Module BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0414Invalid Data Received From Four-Wheel Drive Clutch Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0415Invalid Data Received From Anti-Lock Brake System (ABS) Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0416Invalid Data Received From Vehicle Dynamics Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0417Invalid Data Received From Park Brake Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0418Invalid Data Received From Brake System Control Module ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0419Invalid Data Received From Steering Effort Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU041AInvalid Data Received From Battery Isolation/Voltage Stabilization Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU041BInvalid Data Received From Exhaust Gas Sensor Module ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU041CInvalid Data Received From Rocker Arm Control Module ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU041DInvalid Data Received From Rocker Arm Control Module BCheck soonNetwork & Communication45–120 minutes for initial diagnosis