2021 Mazda 3 BaseFACTORY OEM SERVICE PROCEDURE

Bluetooth® audio function

  1. When the CMU receives the operation signal/detects the switch operation, it sends (1) the control signal to the remote tuner (RT) and a mobile device such as a Bluetooth®-enabled mobile phone or a Smartphone.
  2. When the mobile device such as a Smartphone or a Bluetooth®-enabled device receives the control signal, the digital data is sent (2) to the CMU.
  3. The CMU converts the video signal of the digital data to a GMSL signal and sends (3) it to the center display. In addition, it sends (3) the audio signal to the remote tuner (RT).
  4. The remote tuner (RT) sends (4) the received audio signal to the speakers.
  5. In addition, the center display indicates (5) Bluetooth® audio information based on the GMSL signal. In addition, the speakers output (5) the audio based on the received audio signal.
    G13561498Courtesy of MAZDA MOTORS CORP.
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Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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