SOFTWARE BUG IN macOS Catalina: Bluetooth does not turn on

Question

khushbu19 Author

Level 1

11 points

SOFTWARE BUG IN macOS Catalina: Bluetooth does not turn on

My mac: Macbook Pro Late 2012

macOS version: Catalina 10.15.4 (downgraded from 10.15.6)

The problem:

It shows Bluetooth is disabled with the icon greyed out and a zigzag line across which means bluetooth is unavailable.

In About Mac > System Report > Bluetooth it gives "No information found"

The whole bluetooth Preference Pane has disappeared from System Preferences.

So I had posted about this before. I'll link to that here: https://discussions.apple.com/thread/251574958

Please go over that discussion to understand the problem better.

But with newer discoveries, I decided to create a new discussion.

I opened up my MacBook, removed the battery connection to remove and reinsert the Broadcomm Airport card. Thinking that it was a hardware problem and those steps usually fixed it for others. But no. The problem persisted in the exact same fashion.

Moreover, I have proof it is a software problem.

So let's head back to how the problem started. I connected my bluetooth earphones but faced issues. So I turned bluetooth off. Then the "Turn Bluetooth On" button became greyed out. Bluetooth preference pane disappeared and more.

Basically that single action of turning off bluetooth triggered the software to not recognise the hardware completely.

When I finally had time to look into console and see what's happening, I found this:

The framework WPDaemon is exclusively part of iOS13. But since Catalina I'm guessing Apple has integrated that iOS framework with macOS.

Link to the same framework: https://github.com/w0lfschild/macOS_headers/tree/master/macOS/PrivateFrameworks/WPDaemon/118But

Here's my thought process on what's happening.

This framework must have a variable called CBCentralManager. That variable has been set to turnedOff state (maybe triggered by me turning off bluetooth?). And now that daemon is not powering on.

This has been a problem with Apple iOS developers creating bluetooth enabled applications; here's a few forums discussing the problem:

Why the state of CBCentralManager is always Unsupported: https://developer.apple.com/forums/thread/47230

Incoherent CBCentralManager state in iOS 11: https://developer.apple.com/forums/thread/91664

CBCentralManager is not powered on

CBCentralManager always return .poweredOff state on iOS 11.1.x

A few other errors from above console worth noticing:

Sandbox: bluetoothd(173) deny(1) mach-lookup com.apple.server.bluetooth

Sandbox is used to restrict applications from accessing hardware in the background. I wonder what it's doing denying permissions to core bluetooth itself? I haven't understood anything more on this.

When I ran "sudo bluetoothd" on terminal I get the following in console:

API MISUSE: <CBPeripheralManager: 0x7fedaf615c00> can only accept this command while in the powered on state

Debugging mode:

apple@Khushbu ~ $ sudo bluetoothd -d

objc[4258]: Class PipeInfo is implemented in both /System/Library/PrivateFrameworks/WPDaemon.framework/Versions/A/WPDaemon and /usr/sbin/bluetoothd. One of the two will be used. Which one is undefined.

[bluetoothd][netPrefChanged] ###### Sharing Dictionary doesn't exist

My winning argument, if it was a hardware problem, I wouldn't have gotten a message on the console saying Bluetooth MAC address updated to 44-AB-CC-DD-EE-FF. How did it recognise and update hardware if none is available?

Also Siri still does turn on and off bluetooth when I tell her to.

Anyway I'm still a fresher not even graduated college so I cannot research more extensively. This is a serious bug driving people nuts all over the forums. There are people who get it fixed by changing hardware, clean installs etc. I believe hardware is not the issue in my case. Also didn't want to go into the whole ordeal of clean install, backing up data, installation time just to see the same error again.

Again, I've tried all solutions possible. Please go over my other discussion ( https://discussions.apple.com/thread/251574958 ) to look over those.

I have tried all plist solutions.

I have tried removing whole Bluetooth PAN interface and adding.

I have tried installing different versions of Catalina but nothing works.

Kindly explain what the problem is. I just want to know if my deductions are correct and it is in fact a software bug.

Thankyou.

MacBook Pro 13″, macOS 10.15

Posted on Jul 27, 2020 11:47 PM

Reply

Answer 1

Barney-15E

Level 10

122,084 points

Jul 28, 2020 5:39 AM in response to khushbu19

Try an SMC reset and if that doesn't restore the BlueTooth capability, it is probably a hardware problem.

Reply

Answer 2

LD150

Level 10

99,697 points

Jul 28, 2020 2:40 AM in response to khushbu19

install the combo update 10.5.6

https://support.apple.com/downloads/macos

There is no inherent BT bug in Catalina

Reply

Answer 3

khushbu19 Author

Level 1

11 points

Jul 28, 2020 6:51 AM in response to Barney-15E

As stated in my previous discussion that I linked above which has all the methods I've tried: https://discussions.apple.com/thread/251574958, SMC reset does not fix it for me. The green light flickers on MagSafe charger indicating it was done correctly.

As I said above I do not feel that it is a hardware problem.

The bluetooth and it's preference pane was on and working as I turned on the computer that day. When I clicked on turn bluetooth off the button greyed out and the problem started.

Basically that single action of turning off bluetooth triggered the software to not recognise the hardware completely.

Siri still turns it on and off for me.

Console shows scanning of bluetooth devices is being done. It's the XPC process given to System Preferences that get's invalidated for some reason.

Reply

Answer 4

Barney-15E

Level 10

122,084 points

Jul 28, 2020 1:01 PM in response to khushbu19

As stated in my previous discussion that I linked above which has all the methods I've tried: https://discussions.apple.com/thread/251574958, SMC reset does not fix it for me. The green light flickers on MagSafe charger indicating it was done correctly.

You should have said that in the post instead of all the other useless info. I don't get paid to do research.

Basically that single action of turning off bluetooth triggered the software to not recognise the hardware completely.

Or, your bluetooth module died.

Reply

Answer 5

khushbu19 Author

Level 1

11 points

Jul 28, 2020 11:21 PM in response to Barney-15E

I have mentioned in the post that all the solutions I have tried are in the previous discussion.

I referred the link to it in the beginning:

And in the end:

I'm sorry if you felt everything else was useless info. That is just what I have noticed happening in my computer and wanted to bring to other people's notice so we can brainstorm and conclude things.

This is a problem that started with software. This is a problem that may have corrupted my bluetooth module as you said. But the question of why it happened is still unanswered.

Also if my bluetooth module died it would not give our discoverable items in the console, would not have changed the randomly generated MAC address... I find that as an indication that the bluetooth module still works.

Thanks for your reply.

Reply