iPhone keeps disconnecting from Mac

The solution is as follows:

1. (Make a backup)
2. Shutdown
3. Connect your macbook with power (otherwise this won't work)
4. SMC-reset (power management)
   1. Hold for 15 seconds: cmd + alt + shift + power
   2. If you have a MacBook with a magsafe adapter thats fully charged you will see the light change from green to orange for less than a second this means the reset has succeeded.
5. VRAM reset (also known as PRAM reset if I'am not mistaken)

   Power on and immediately pres and hold: cmd + alt + p + r. This wil restart the machine, hold these buttons until the machine has tried to bootup two or three times then let go.

The problem could comeback but just use this 2 minute trick and your good to go.

Please let me know of this worked for you!

My hardware: MacBook Pro 15 inch 2015 (fully spect). Had this problem with: iPad 2017, Iphone 7+, Ipad 4, Iphone 6. All works well after this reset.

Given that there's little in the way of official support here I'd recommend anyone who's still having this issue to head over here: https://forums.macrumors.com/threads/ipad-keeps-connecting-disconnecting-from-ma c.1851453/#post-25257291

Settings > General > Reset > Reset Location & Privacy. This will reset your location and privacy settings and require you to set up a trust relationship with the PC/laptop again.

This fixed it for me (the issue was still there after an upgrade)

I had this problem connecting iPhone to Mac to any of the Mac ports. Charging sound would go on & off with a regular pattern. Was using an aftermarket charging cable. I switched to a new apple cable and it worked perfectly.

Clean both ends - lightning and usb with alcohol. I had 3 cables doing this, even a brand new one. After cleaning I have no problems. Thought the USB port was broken.

The only solution has worked for me was to connect iPhone (or iPad) throughout external USB hub. Mac immediately connected with my iPhone without a problem.

Thanks. Resetting Privacy and Location on iPhone seems to have fixed. Been dealing with this issue for months. About 75% of the time when I tried to charge my iPad or iPhone using my MacBook, it goes charging, not charging, charging not charging, every second back and forth. Seems like a bug to me. Tried different cables, USB ports.

Apple needs to address this, in my opinion, by at least displaying a popup to change whatever privacy/location setting is causing this.

Just charge your phone till green which is about 20% or more, try again connect to your Mac. There's one guy suggesting this idea and I did so. It worked for both USB ports. Why does my iPad keeps connecting and disconnecting from the new late 2013 iMac

this helped me https://support.apple.com/en-us/HT204095

I had the same problem, Apparently it got fixed when I tried with original lightning cable.

Unplugged all other devices before plugging in the iphone worked for me.

If you are using the Xcode or iOS Simulator, turn it off.

I blew as hard as I could for several times into the USB end of my iPad cable and it worked! I thought of this idea because of the amount of dust in my office. I thought it was causing a poor connection. It did it! Hope your case is the same

Launch the Console application in any of the following ways:

☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)

☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.

☞ Open LaunchPad. Click Utilities, then Console in the icon grid.

Make sure the title of the Console window is All Messages. If it isn't, select All Messages from the SYSTEM LOG QUERIES menu on the left. If you don't see that menu, select

View ▹ Show Log List

from the menu bar.

Click the Clear Display icon in the toolbar. Then try the action that you're having trouble with again. Select any messages that appear in the Console window. Copy them to the Clipboard by pressing the key combination command-C. Paste into a reply to this message (command-V).

When posting a log extract, be selective. In most cases, a few dozen lines are more than enough.

Please do not indiscriminately dump thousands of lines from the log into this discussion.

Important: Some private information, such as your name, may appear in the log. Anonymize before posting.

I seem to resolve this issue on my 15" 2015 MacBook pro by unhooking it from charger and all other peripherals. It then stopped the disconnect connect cycle on the iPhone. I could then plug the power and peripherals back in.

I can confirm that this does indeed work. And I discovered that it will also work if you plug in only one device IF it has enough juice in it. Like around 60% or more. So if you plug in your ipad, make sure it has at least 60% battery. Same with the iPhone.