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iPhone connects and disconnects from Mac

Hello,


When I plug in my iPhone to my Macbook pro, it repetitively connects and disconnects. Therefore I cannot charge my phone through my computer anymore.


I own this iPhone since decembre 2018, and this issue only appeared this week. However when I plug in my iPhone to a wall outlet, it charges perfectly. I also noticed that there is a lag time before my phone starts charging when connected to my Macbook (before disconnecting right away, and then reconnecting etc).

I tried to connect my iPhone to both USB ports of my Macbook, with many different Apple lightning cables and also my Anker cable (MFI certified), but the issue substains. I plugged in my mother's iPhone 6 to my Macbook and it charged perfectly. I plugged in my iPhone to my brother's former Macbook pro (15" from 2008) and my iPhone could charge normally.


Here everything I tried to resolve this issue (which failed by the way) :

- I shut down and turned on my computer and my phone.

- I reseted location and privacy of my phone (Devices rapidly disconnect/reconnect - Macbook Air Mid 2013).

- I also restored my phone.


Could anyone tell me a solution?


I specify that I have a 256Go iPhone X under IOS 11.2.5 and a 13" retina Macbook pro (mid 2014) under High Sierra 10.13.3.


[Re-Titled by Moderator]

iPhone X, iOS 11.2.5

Posted on Feb 10, 2018 1:34 PM

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Question marked as Best reply

Posted on Aug 28, 2019 4:20 PM


Sep 11, 2018 8:27 AM in response to MélodyH

Connect your iphone to your Mac.

Go to Activity Monitor --> Search for usbd --> Force quit it.



The above worked for me. To add a bit: You click on the upper right of your screen where there is a magnifying glass and search "activity monitor." Keep "CPU" highlighted. Type "usbd" into the search box. Now plug in your phone. It'll connect, reconnect, connect, reconnect and so you have to be quick and double click on "usbd" even though photos and itunes keeps popping up. then once you've successfully double clicked "usbd," click on "quit" which takes you to a screen that says "force quit" and click "force quit."


I also took the recommendation of going to my iphone and settings-->general-->reset-->click on reset location and privacy.


I did both and it worked.

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276 replies

Feb 17, 2019 1:58 PM in response to MélodyH

I have the same problem. I tried doing things below, but it didn't work.


The problem was fixed when i switched from a third party usb cable to one made by apple and pushed the end of the charger a little. Before that, i was using an anker charger(tried doing ^ but it didn't work).


The small battery symbol on the top right of my iPad was going on and off, so I thought that there was some problem with the connection from the usb cable to the computer.


Cleaning out the hole that the usb goes in, or pushing the usb end a little next to the computer's input will cause the cable to have a secure connection from the pc/laptop to your iPhone/IPad.


i hope this works for you.

Feb 25, 2019 7:29 AM in response to Executorbot

The thing is, I am using Apple cables, and other i-devices seem to be able to connect to my MacBook Air just fine. This also happened with a previous iPad that I had the same info in. The problem, for me, is that something is wrong with the internal software? (I’m guessing, since anything else works and after backing up my 2nd iPad doesn’t work).

Mar 11, 2019 3:41 PM in response to julionguyen

I'm having the same issue here but just with my husband iPhone 7 Plus. Mine works pretty fine but it's an iPhone 6.


MacBook Pro Retina, 13-inch, Mid 2014 - MacOS Mojave 10.14.3 with iTunes 12.9.2.5

iPhone 7 Plus iOS12.1.4

iPhone 6 iOS 12.1.4

Apple lightning cable


One thing that I've noticed is that killing usbd via Activity Monitor worked here but it turned the personal hotspot on in the iPhone 7 Plus. And when I turned the personal hotspot off, the issue restarted immediately. Have anyone noticed that too?

May 10, 2019 6:14 PM in response to MélodyH

I followed the suggestion regarding power. My iPhone x was at 37% and pulled the cable from my Macbook pro, plugged in a powered USB hub, then plugged my iPhone into the hub. No more issues.

It ****** me off that Apple couple not provide an answer about this problem and we had to figure out how to get around it. I wish Tim would stop worrying about promoting his gay agenda and get back to running the business.

Jul 19, 2019 6:39 AM in response to MélodyH

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.

Jul 20, 2019 5:21 PM in response to MélodyH

I have tried literally everything I read on internet and still couldn’t fix it, so I turned off my macbook and turned it back on while iphone was still plugged in and it connected and stayed connected..when I unplugged it and tried it again it kept doing the same connecting/disconnecting thing. So I would suggest just restart your MacBook while iphone is still plugged in on the usb port and see if it solves the issue when it turns back on.

Jul 29, 2019 5:49 PM in response to MélodyH

I was having this exact issue and my brother and I tried ever troubleshooting thing you could think of and nothing would work. I finally tried again just for the sake of it after my phone was had charged up some and it now connects with no problem! When I was initially trying to connect my phone was close to dying and only had about 13% remaining, but after I got 50+% CHARGED no issues what so ever!


I HOPE THIS HELPS SOMEONE!!!

:)

Aug 23, 2019 5:07 AM in response to MélodyH

This is most annoying. I'm having these issues with a USB connection between iPad or iPhone connecting to iMac. Only solution is to force quit USBD from Activity monitor (or terminal method). This solves it while iPad or iPhone is connected. Once devices are disconnected, this will happen all over again when next plugged in.


When force quitting USBD and as an indicator that things are not right when plugging in device afresh, device constantly asks me to enter PIN number to trust device...


It's not - energy based (ie battery less than 60%)

It's not - a cable issue

It's not - Reset Location & Privacy settings on iPhone or iPad

It's not USB port on iMac - others have same results


Because it doesn't happen with same devices and cables at all when I connect iPhone or iPad to MacBook Pro.


Restarting iMac doesn't help either.


Any ideas what can be done here?


Thanks

Sep 9, 2019 4:30 AM in response to MélodyH

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...

iPhone connects and disconnects from Mac

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