I have a MacBook Pro (2015), and an iPhone 7 Plus.

The problem is the following: If the iPhone is connected to my Mac, then whenever I run an app via XCode, or the Mac is just transferring data, the iPhone starts disconnecting and connecting (the battery icon indicates it), and the data transfer fails.

First I thought that this was a cable issue, because If I adjust the cable in a certain position then it works, but I realized that it is not:


  • I bought brand new cables

  • I cleaned the USB port of the Mac

But still nothing

It is really annoying.

Sometimes it gets fixed if I unplug & reinsert the USB like 5-7 times.

  • I have a feeling that your USB port has a physical problem. This post has more details on this. You can test this by connecting a USB drive and attempting to transfer large amounts of data to/from the drive. If it fails, it's the port.
    – Allan
    Dec 13, 2018 at 21:27
  • I ALWAYS experience this, and I know many fellow people who experience this. You are not alone in this issue. I may think it is a problem with either the the cords as a whole or hardware. I would love to hear from someone who was had this problem and solved it. Also, I have an iPhone 6s and a MacBook Air. Dec 13, 2018 at 21:39
  • This question had some helpful answers: apple.stackexchange.com/q/298573/45492
    – n1000
    Dec 21, 2018 at 8:12

2 Answers 2

  1. Disconnect your iPhone or iPad.
  2. Open Terminal and type
sudo killall -STOP -c usbd
  1. Happily connect again your devices.
  • 1
    1 year later but I still have the same issue with the latest macOS, latest ios, latest devices, new cables... Dec 2, 2019 at 12:20
  • Work like magic
    – alper
    Aug 7, 2021 at 17:43

Tried really everything, the only thing that works is charging my iPhone to 100%, than the iPhone 11 or 8 does not disconnect anymore from my Mid 2015 Macbook. So and hoc connecting is a problem, as well as charging your phone via the laptop.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .