Question about HA5476 Vivid11 Firmware / MCU

• Vivid11
• RAV4, Audio, Firmware, MCU

• RS

  Richard Smith

  4/27/25, 10:27 PM

  Hi, I've had the head unit for my RAV4 for two years and it's been a great addition to my car.

  I recently got hit by the "No voice in Android Auto" bug and have tried every debug path I can find.

  So then I try updating the MCU but I made the big mistake and applied a wrong version (my bad).

  So when I re-apply MTCH_HA (4.04) it works but now the screen is flickering because I wiped the dmcu.ext.

  So my question is, please tell me the correct screen:? value for that model (HA5476-Vivid11).

  Also maybe you can also tell me if 4.04 is still the most recent version, thanks.

  And, while I have the unit in this state (I wiped but haven't re-applied all my customizations yet) maybe you can tell me if there's anything else I can do about the voice guidance issue (it really seems like a Zlink bug to me).

   

   

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• RS

  Richard Smith

  4/28/25, 3:04 AM

  I made some progress. Setting "screen:12" in dmcu.ext fixed the display issues.

  It looks like wiping the unit brings back the Android Auto voice guidance, but in order to stop the bug you must prevent the Google app called "Speech Recognition & Synthesis" from ever getting updated. Even a single update will trigger the bug and uninstalling / removing updates does not fix it. I need to test for a few more days of normal use to make sure it's fixed.

  Here's my current info:

  

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