How to fix the no sound issue after upgrading the Koason Mercedes Benz NTG4.0 Android Touchscreen?

Jul 04, 2025 by Koason

Optic Fiber Relocation (if applicable)

If your vehicle has an optic fiber system, it must be relocated to the Android harness. (Skip this step if your vehicle doesn't have optic fiber)
https://www.koason.com/blog/how-to-relocate-optic-cables-on-mercedes-bmw-android-display-upgrade

AUX Port Connection (Mercedes Models)

Some Mercedes-Benz models require connection to the AUX port for audio output.

Audio Settings Configuration

For NTG4.0 Systems: "Automatically switch AUX" mode is not supported - must be set to manual mode.
 
Setup varies by Android version. https://youtu.be/6iieNn_cwT4

Setup Option 1:

Path: Settings → System → AUX Settings
  1. Deselect "Automatically switch AUX" (switch to manual mode)
  2. Verify AUX Position is set to "0" (default - typically no change needed)
  3. In NTG menu: Select "Audio-AUX" → Switch to Android system for audio output

Important Note:
  1. "AUX Switching scheme" = Amplifier selection:
  • Scheme A: Alpine systems
  • Scheme H: Harman systems
  • Customize: Other brands

Setup Option 2:

Path: Settings → Factory (code "2018") → Vehicle → AUX Switching Modes
  1. Select "Manual" (typically default)
  2. Verify AUX Position is "0" (default - typically no change needed)
  3. In NTG menu: Select "Audio-AUX" → Switch to Android system for audio output
Important Note:
  1. For "AUX auto switching": Select according to your head unit brand.

Android System Volume Verification

  1.   Check and adjust the Android system volume as needed: