Diagnostic library
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Search the code from your scanner, then narrow the library by system, severity, or code family.
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 8209–8232 of 8256
U0003High Speed CAN Communication Bus Positive OpenCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0004High Speed CAN Communication Bus Positive LowCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0005High Speed CAN Communication Bus Positive HighCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0006High Speed CAN Communication Bus Negative OpenCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0007High Speed CAN Communication Bus Negative LowCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0008High Speed CAN Communication Bus Negative HighCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0009High Speed CAN Communication Bus Negative Shorted to PositiveCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0102Lost Communication With Transfer Case Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0103Lost Communication With Gear Shift Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0104Lost Communication With Cruise Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0105Lost Communication With Fuel Injector Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0106Lost Communication With Glow Plug Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0107Lost Communication With Throttle Actuator Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0108Lost Communication With Alternative Fuel Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0110Lost Communication With Drive Motor Control Module ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0112Lost Communication With Battery Energy Control Module BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0113Lost Communication With Emissions Critical Control InformationCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0114Lost Communication With Four-Wheel Drive Clutch Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0115Lost Communication With ECM/PCM BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0116Lost Communication With Coolant Temperature Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0117Lost Communication With PTO Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0118Lost Communication With Fuel Additive Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0119Lost Communication With Fuel Cell Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0120Lost Communication With Starter/Generator Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosis