iPhone connects and disconnects from Mac

same here. i have 4 cables and all of them, the same thing happens. keeps connecting and disconnecting. this is not a problem of our phones or computers. im sure its something they did in the os.

This is so frustrating. Tried all of the above. Cahrged an uncharged. It worked a couple of times ... and couple of times it was madness... so annoying.

I've had the same problem for years. MacBook Air and iPhone 8 plus now. I've tried everything, and the only thing that has worked is using a genuine Apple USB cable. What a joke.

I had the same issue. I found that if my phone is fully charged (don't know over which %), and I changed the settings in iTunes to NOT sync automatically, no more rapid disconnecting.

I charged my phone fully, then made the following adjustments to my settings to not sync automatically in iTunes. Now works perfectly.

this worked for me also,

On the mac, go to settings>Network> iphone USB> then uncheck the box that says "Disable unless needed"

Try terminal :

sudo killall -STOP -c usbd

....worked like a charm for me....

Look at this article If you see "Software update is required to connect to your iOS device" on your iPhone, iPad, or iPod touch - Apple Suppo…

I found a workaround (didn't solve but you can charge like theres nothing wrong IF you do this every time that happens).

When it starts connecting and disconnecting you put the iPhone on Low Power Mode: ON and reduce the screen brightness all the way down tils its dark. You'll notice that it will stop doing the Connect/disconnect dance and just charge, slowly but still charge.

Worked for me for some time now. Usually original cables and wallplug doesn't need this workaround. Problem shows up for me when using not original cables or usb from pc, macs, other gadgets chargers and so on.

If it works for you, please let me know. I wanna spread the word cause I never found a workaround on the internet and wanna help those frustaded iPhone users.

At.

Further testing shows that just force quitting USBD from Activity Monitor only works temporarily. Once phone is disconnected and then reconnected, the problem returns. But you can resolve this issue more permanently, by using this terminal command whilst phone is connected via USB:

sudo killall -STOP -c usbd

This should be fine until you update OS.

Now all that remains is the annoying "Trust this computer?" alert every time I plug phone in...

I feel a little silly to report that ...

• I only tried two different Lightning-USB cables to connect between my iPhone XR and my late mid 2015 MacBook Pro (and the problem remained)
• third time lucky, a legit RCA cable works just fine !!! :-)

So far, the connection works fine, I had no need to apply any other solutions mentioned in this discussion topic.

I wish a simple solution like mine would work for all of you. Good luck and don't give up !

Bronco

Fixes devices connecting and disconnecting rapidly with iTunes

Made the script , just save to desktop

Open Automator ---- Run AppleScript --- Add Script --- Save as application in Desktop

Enter System Preferences ---- Go to User & Groups --- Click on your User ---- Login Items ---- Add The Usb Fix . All Done

------------------------------------------------------------

tell application "Terminal"

do script "sudo killall -STOP -c usbd"

delay 2

do script "Your Mac Password" in front window

delay 1

do script "killall Terminal" in front window

end tell

------------------------------------------------------------

Tutorial:https://www.youtube.com/watch?v=IF3eVmLdqpI

Hope you enjoy it :)

This issue began for me when I plugged in the iPhone and was given the message in iTunes that the laptop needs to update software to be able to connect to the iPhone. During the update I accidentally unplugged my iPhone from my MacBook Pro while the laptop was updating software. I have tried everything listed here in this thread except for the iPhone USB setting because I could not see it in mt network settings. Laptop is a 2015 MacBook Pro running Catalina and iPhone is an 8 Plus running IOS 14.1. I spoke to Apple support and they recommended I re-install Catalina in recovery mode. Before I do that I was hoping there may be another suggestion from the community.

I was having this issue, very frustrating. I have a 5-year old iMax and my iPhone would not stay connected for more than a couple of seconds. After trying everything listed in this thread with no success, I found that if I plug it into the USB on my wired keyboard all problems went away. I am just backing it up so I can get my new iPhone 12 on like, hopefully this issue will go away.

Same with iPhone 12 mini (15.0) on M1 Mac (11.6).

Intermittently disconnects from Finder and Image Capture, sometimes mid-sync.

Important:

• works fine on an old MacBook Air with macOS Catalina, same cables.

• other iPhones / iPads all work fine on the M1 Mac Mini with the same cables.

• tried different cables (USB, USB-C) and ports

• only original Apple cables, undamaged

• tried without USB hub

• tried rebooting all devices

• tried resetting the privacy / location settings on iOS, trust computer again.

• tried killing the usbd process

• tried creating a new user on the Mac

In System Preferences -> Network I found a couple of Thunderbolt bridges and "iPhone USB" devices that all had red or orange indicators. I deleted them all an now it seems to work.