16-inch MacBook Pro Bluetooth issue

Connecting an external BT dongle causes the internal BT hardware to fail, which requires Apple to replace the Logic Board on the 2019 16-in MBPs.

[Edited by Moderator]

jjcinaz wrote:

Yes, the WiFi works just fine after the BT is dead.

In that case, the only solution is a Logic Board replacement.

Couple of us are having the same issue, used a USB device with bluetooth attached on a MBP 16 and then the internal bluetooth stops working.

Plug the USB device with bluetooth back in and the devices all work again.

Anyone found a way resolve this ?

Hi, I got an update from the Apple Store. Turned out it is indeed a hardware problem and they are going to replace the whole logic board now. That should definitely fix the problem. But I am kind of scared to use the Bluetooth dongle again. I saw a terminal command you could execute to prevent the Bluetooth controller from switching automatically, but not sure if that works. I have to wait now until they have replace the logic board. Hope they are fast

Thanks, Apple Support has said its a hardware issue to me too. Booked in at an Apple Repair Center for them to look at it on Friday. I suspect it will be the same approach of replacing the logic board.

I found a project that will reflash the Broadcom Bluetooth module. Its a bit complex and so getting some help, will let people know if it helps - https://github.com/the-darkvoid/BrcmPatchRAM

The working theory from the geniuses at the Apple Store was that using bluetooth switching to try to connect an external Bluetooth dongle was tripping something in the T2 security chip in a non-recoverable way. Please see my post from a couple(?) weeks back about what I went through with this (two logic board replacements).

Thanks so much for this. It's got mine working again, but not without some drama.

I ordered the previously linked dongle from ebay and put it in. It got so hot it melted and burned. I'm going to put this down to more bad luck. I then found a 2.1 dongle in stock nearby and went and grabbed it. It's done the trick.

There is one caveat thus far, which is that my Logitech Craft keyboard won't pair with the Mac via bluetooth. Logitech Options pairing tool says 'Your Mac does not support Bluetooth Smart devices', which I think means is not 4.0+.

I'll persevere as it may be unrelated to this overall issue.

EDIT - Yep, fixed with a reboot. All working!

One thing I noticed in your instructions/video:

AntiHawk wrote:

Hi,

I changed the procedure a bit as NVRAM reset was pain to do as I have firmware password set.

Doing SMC reset instead.

https://www.youtube.com/watch?v=2elFJmqJJtI

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1. For demo purposes I have already broken my internal BT with CSR 4.0 BT dongle

2. Disconnect CSR 4.0 BT dongle if it is still connected

3. option+shift+bt icon - debug - reset the bluetooth module

4. Run “sudo rm /Library/Preferences/com.apple.Bluetooth.plist”

5. Shutdown your Mac and do SMC reset

1. My procedure is following as I have filevault enabled

1. Start your Mac

2. Wait until filevault login appears

3. Press option+cmd+RIGHT SHIFT for 7 seconds

Number 3. should be option+control+RIGHT SHIFT, not CMD. At least according to the Apple instructions here.

Thanks again for all your work on this.

I tried everything I read here, nothing worked. I also upgraded so Big Sur, but no changes.

In the end I shut down my MacBook, unplugged everything and started the Hardware diagnostics with Power on and Press D. After 3 minutes it said everything is fine, I didn't expect anything, but I restarted and suddenly Bluetooth worked again.

Maybe it was a coincidence, but give it a try ;)

My problem was solved by logic board replacement.

Now need to make sure to never plug a bluetooth dongle to an mbpro.

Hi, so I finally got my MacBook back and it works great. The command I found was quite helpful, I can pass it through to my virtual machine without macOS picking the usb Bluetooth dongle up and use it.

The command is this just paste it into terminal AT YOUR OWN RISK:

sudo nvram bluetoothHostControllerSwitchBehavior=never

to restore to default run this AT YOUR OWN RISK:

sudo nvram -d bluetoothHostControllerSwitchBehavior

Reboot after you set this variables

I had the same issue, final solution that worked was for the Apple Service centre (No Genius Bars in New Zealand) was to run the special diagnostics that only works in store on a special wireless network.

They ran two different types, see my post above and then it worked.

Still working to this day !

Got my macbook back within 1 week!

Logic Board replaced...

Now Im sitting here and think about what to do...

I got a brand new Surface Laptop 3 15 inch i7 here...

Sell Mac? I wanted to but now I think maybe to keep ?! But im not sure if it is the best decission ....

I just spent the past 2 hours trying all possible combinations of the steps you described to no avail.

macOS just won't recognise the internal module as a HCI Controller anymore.

Using the dongle is the only way to get partial/unstable Bluetooth.

With the Bluetooth Explorer I can see that macOS will pick some BLE devices nearby without a dongle but won't successfully connect to any of them.

I've got the same issue and this is the first day of owning my Mac.

I have been able to get limited connectivity back by doing the following:

• Plug in the BT dongle
• Connect my wireless mouse to dongle BT
• Disconnect dongle
• Connect mouse via lightning cable
• It then shows as charging in the BT preferences list
• Disconnect cable
• Put mouse on top of keyboard (over the touch display bar thingy seems best)

By doing this I get very bad, laggy movement and clicking, like it has a super weak signal.

I also paired to my phone this way and tried sending a file to it from the Mac. It always failed to connect at all unless phone was rested on keyboard. I managed to send a photo across at 1-2kb/s.

@jamiefromkirkcaldy,

Apple didnt even pick mine up, they will not fix it. Anyway it was fix by this little 2.0 dongle device. but the main issue remains Apple didnt want to fix the computer just for the bluetooth.

Steve died and with it Apple customer care.