Persistent macOS CPU Hog accessoryupdaterd

I updated from Ventura to Sonoma and, as expected, experienced a problem. My expertise is very limited, but If anyone has suggestions, I'll be grateful.

I found this process consistently hogging 35% CPU. accessoryupdaterd

The user owner is listed as _accessoryupc

It's persistent. Activity Monitor kills it but it's a daemon and returns in seconds.

I've tried everything I know with no luck, including days of searches, online terminal unload suggestions, multiple calls to Apple, uninstalling a reinstalling apps that might be associated, and as some have suggested it's associated with Bluetooth, forgot all Bluetooth accessories and restarted, checked if it might be malware, all with no luck. It seems to be a protected process.

It launches in Safe mode, BUT ONLY LAUNCHES IN ANY MODE WHEN LOGGED IN TO MY USER ACCOUNT.

Via Apple support, I created a second user account where the process does NOT launch. While neither myself or Apple could find a way to stop the process, Apple suggested a full OS reinstall but warned that the problem might simply reoccur from Time Machine user records.  Not a very promising task. And I desperately don't want to manually rebuild the entire system around a new user account.

So I'm hoping that I can find the triggering culprit in my user data and stop it there, but any suggestions would be appreciated.

The protected process is called by an alias located here:

/System/Library/PrivateFrameworks/MobileAssetUpdater.framework/MobileAssetUpdater

It calls a protected plist script here:

/System/Library/LaunchDaemons/com.apple.accessoryupdaterd.plist

Which launches the protected exec process located here:

/System/Library/PrivateFrameworks/MobileAccessoryUpdater.framework/Support/accessoryupdaterd

Here's the plist and associated files launched:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>EnablePressuredExit</key>
    <true/>
    <key>GroupName</key>
    <string>_accessoryupdater</string>
    <key>Label</key>
    <string>com.apple.accessoryupdaterd</string>
    <key>MachServices</key>
    <dict>
        <key>com.apple.MobileAccessoryUpdater</key>
        <true/>
        <key>com.apple.MobileAccessoryUpdater.defaultClient</key>
        <true/>
        <key>com.apple.accessoryupdater.launchauhelper</key>
        <true/>
        <key>com.apple.accessoryupdater.observer</key>
        <true/>
        <key>com.apple.accessoryupdater.uarp</key>
        <true/>
        <key>com.apple.accessoryupdater.uarp.launchagentlistener</key>
        <true/>
        <key>com.apple.accessoryupdater.uarp.standaloneCommandListener</key>
        <true/>
    </dict>
    <key>ProcessType</key>
    <string>Adaptive</string>
    <key>ProgramArguments</key>
    <array>
        <string>/System/Library/PrivateFrameworks/MobileAccessoryUpdater.framework/Support/accessoryupdaterd</string>
        <string>120</string>
    </array>
    <key>RunAtLoad</key>
    <true/>
    <key>UserName</key>
    <string>_accessoryupdater</string>
</dict>
</plist>

 

https://www.reddit.com/r/MacOS/comments/18bgp6n/constant_30_cpu_use_from_accessoryupdaterd/

https://discussions.apple.com/thread/254013446?sortBy=best

https://apple.stackexchange.com/questions/309329/what-is-mobileaccessoryupdater-and-why-it-runs-on-my-macbook

Edited by greg18, 24 May 2024 - 03:23 PM.

Thanks for the kind reply.

Sigh.

This problem has not only been exhausting, it's getting compulsive.

So I already found those references. The only one with an actionable answer was the stack exchange suggestion to unload the process using Terminal. But after dozens of efforts, I get consistent errors. It will NOT unload on command. It's stubborn, apparently system locked, and persistent. That's why I'm scrounging from forum to forum hoping for a solution.

But sincere thanks for the links.

35% is not that much in use. It is not a normal running process unless you have some kind of mobile device connected to it via USB, or BT

Thanks for the reply. The problem is that after studying this with the Console app, it launches, then encounteres an error, terminates, and relaunches every two seconds, adinfinitum. It's just doesn't seem like a smart thing to let it run on. It was right after an update to Sonoma that caused this, so I contacted Apple twice. The best they could offer was to setup a new account or reinstall the OS.