How do I revert back to the internal bluetooth controller

[cloudnoize]

When the Mac mini 2018 was released, I was experiencing Magic Mouse 2 issues (choppiness, etc), like many others, so I decided to get a Bluetooth 4.0 dongle (IOGear GBU521) and see if the problem would go away. It did...

I plugged in the new adapter, went into Bluetooth Explorer, under "HCI Controller Selector" selected my adapter "Broadcom Corp, Location ID XXXXXXX", made it ACTIVE and I was good to go. From memory, I don't believe I did anything else to get this to work. One thing though. When I would reboot, it would go back to the internal Bluetooth controller so after reading about it, I used this Terminal code sudo nvram bluetoothHostControllerSwitchBehavior=always and all was good...

A year later and after moving my workstation around, I would like to go back to using the internal Bluetooth controller but it seems I can't.

This is what I did... I unplugged the dongle and the mouse and keyboard no longer show under the Bluetooth devices panel, for me to Connect to. So I tried the following...

1- Unplugged all devices and hubs going to the Mac mini except for a wired mouse, keyboard and monitor so I can set things up.

2- I entered this code in Terminal sudo nvram -d bluetoothHostControllerSwitchBehavior (to go back to the default setting).

3- I trashed com.apple.bluetooth.plist & com.apple.bluetooth.xxxxxxxxxx (random numbers and letters)

4- Shift-Option to Debug (Reset the Bluetooth Module, Factory reset all connected Apple devices, Remove all devices) re-booted.

5- PRAM (Option-Command-P-R)

6- SMC (Unplug AC cord, 15 seconds, replug and wait 5 seconds) Reboot.

I'd like to add that I tried installing a fresh copy of 10.15.5 on anther SSD, with nothing else installed, and still, I can't get the internal Bluetooth controller to see my devices. If I do add a dongle (4.0, 2.0), all is fine.

Also, my own Diagnostics (press D when booting up) came back with no issues.

I'm not sure what I may be missing here but all that I've tried so far isn't working and I've tried it multiple times. Maybe there's a Kext file I need to delete (replace) but I'm not sure what to do. I know I can plug the dongle back in again, and the mouse and keyboard will show up in the Bluetooth panel but I shouldn't have to anymore. Actually, when I also plug in an older Bluetooth 2.0 dongle, I'm able to connect devices to it. Very strange.

Any help or advice would be appreciated.

Thank you.

 

[XianPalin]

I think I am having a similar issue with my Macbook Pro 2020. I had the first replaced because the bluetooth stopped working. Now it's stopped working on the replacement.

Your post made me think that maybe the reason bluetooth has also died on my second laptop is because I sometimes connect it to a monitor that has a usb bluetooth adapter plugged into the back of the monitor. So I think my problem is the same as yours, but on a new laptop.

Basically USB bluetooth adapters seem to kill the internal bluetooth. On the first laptop I went through almost everything you did - SMB, PRAM, reinstall, erase all volumes and reinstall, etc. No luck either.

Could it possibly be damaging the actual internal bluetooth? Seems super strange.

 

[cloudnoize]

From what I understand, it may not be damaging the internal Bluetooth but rather have it in "off" state. Why I say this is because the internal Bluetooth (with dongle pulled out) is still being seen under About This Mac, System Report, Bluetooth. If we were damaging the internal module, that info wouldn't show up and Diagnostics would say there's an issue with Bluetooth. I wish I knew if we could "zap" or "flash" the Bluetooth module and put it back to Default.

 

[XianPalin]

I sent laptop #2 in for repair. I also included the bluetooth adapter I had in hopes that maybe it would help them figure out a more general fix. I just got the laptop back with some notes saying they replaced the entire logic board and the touch ID sensor, all because Bluetooth wasn't recognized.

 

[gages]

I think it is
sudo nvram -d SkipIOBluetoothHostControllerUARTTransport

 

[XianPalin]

Unfortunately I don't think that works in this scenario. When I had the problem I deleted every NVRAM setting related to bluetooth that I saw (sudo nvram -p) and rebooted and it was still broken.

 

[djapnrcpro]

Xian, did you get this issue resolved?

 

[XianPalin]

They had to replace the logic board. I never tried to hook up my bluetooth USB stick to my laptop again. Bluetooth has been working fine since the replacement.

 

[Atchoo]

2- I entered this code in Terminal sudo nvram -d bluetoothHostControllerSwitchBehavior (to go back to the default setting).

Any help or advice would be appreciated.

Thank you.

Hi. The default value is actually:

sudo nvram bluetoothHostControllerSwitchBehavior=never

Just in case anyone else is having bluetooth controller problems. I realize this thread is quite old.


Andreas