Apple - Macbook Pro Bluetooth not available after plugging in a dongle

This seems to be a general problem with motherboards of 2019 models.

Check this link: https://discussions.apple.com/thread/250944058

There are many people including myself that has this problem.

It seems like the only resolution to the problem is a motherboard replacement.

I have exactly the same error and problem.

I used a dongle that supports mac.

Just for information: I have tried to reinstall, clear t2 chip using xartutil --clear-all, nvram reset, smc reset and so on.

Seems motherboard replacement is the only resolution.

Update: A new method to fix this problem has been revealed on the apple forums: https://discussions.apple.com/thread/250944058


In my case, the answer was to replace the whole motherboard along with all the internals as they are glued to the laptop. This includes CPU, GPU, SSD and other expensive components. What a waste just because of a small BT chip is dead.

The company doing the maintenance told that they were unable to detect anything was wrong using their tests, but could not get the BT working. Glad it fell under warranty.


I have been able to solve this exact problem by:

  1. Shutdown the Mac completely
  2. Plugin any supported usb bluetooth dongle while Mac is off
  3. Start the Mac and login to the system
  4. Use bluetooth to find and connect to some bluetooth device (propably optional step)
  5. Remove the usb bluetooth dongle
  6. Internal bluetooth started to work again normally

Also if this doesn't work first time you might want to repeat few times and try combinations where you shutdown the Mac with and without the dongle and startup the same way with and without the dongle.

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Before this I also did following:

  • Reset NVRAM
  • Reset SMC
  • Reset the bluetooth module
  • Remove bluetooth.plist
  • Used bluetooth explorer.app
  • Booted to recovery (CMD+R) on startup

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I think this is some kind of firmware related problem where call to re-enable internal bluetooth is not executed properly in certain situations leaving the bluetooth in unusable state.

Solution in my case was insipired by similar headphone jack problems on older models where Mac thought that jack was plugged in and disabled onboard speakers even if no jack was connected.