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Audio System - Diagnostics: Pre-Check

  1. IDENTIFICATION OF NOISE SOURCE 
    1. Identify the condition under which the noise occurs, and check the noise filter on the related part.
      NOISE OCCURS CHECK

      Condition In Which Noise Occurs Noise Source
      Depressing the acceleration pedal increases noise, or stopping the engine erases the noise immediately. Generator
      Noise occurs during the A/C or the heater operation. Blower motor
      Rapid acceleration during driving on the unpaved road or after the IG switch is turned ON makes noise. Fuel pump
      Pressing and releasing the horn switch, or keeping pressing the horn switch makes unusual noise. Horn
      Stopping the engine erases small noise that has been heard. Ignition
      Noise occurs synchronously with the turn signal flash. Flasher
      Noise occurs during the window washer operation. Washer
      Noise occurs during the engine running, and it continues after the engine is stopped. Engine coolant temperature sensor
      Noise occurs during the wiper operation. Wiper
      Noise occurs when the brake pedal is depressed. Stop light switch
      Others. Static electricity stored on the vehicle
    2. Reference:
      • Make sure first that there is no noise from outside. Failure to do so makes it difficult to detect the noise source and leads to misunderstanding.
      • The noise should be removed in descending order of loudness.
      • Setting the radio in a tuneless state makes it possible to notice the noises, which help to recognize the phenomena.
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