Audio System Symptom Troubleshooting - Volume does not change

NOTE: 

• Check the vehicle 12 volt battery condition first .
• Set the fader and the balance positions to the center.

• 1. Problem verification:

  - 1. Turn the vehicle to the ON mode.

  - 2. Listen for sound from the speakers.

  - 3. Operate the volume knob to see if the volume changes.

  Does the volume change?

  YES 

  Intermittent failure, the system is OK at this time.

  NO: With navigation

  Replace the audio-navigation unit .

  NO: Without navigation

  Replace the audio unit - Refer to: Audio Unit Removal and Installation(With Display Audio)Audio Unit Removal and Installation(With Normal Audio) .