iPad connects/disconnects to MBP

[MacInWin]

This post is just for information. I wanted to make a backup of my iPad Mini 4 today so I could update the iPadOS. So I connected to my MBPr mid-2015 with a cable and opened Finder (Big Sur also updated, so 11.4). The iPad was fully charged. But when it connected it would not stay connected. Connect/drop, connect/drop, over and over. I was unable to get the backup done because the cycling on/off was so short that I couldn't even click on the iPad name in the sidebar of Finder!

So I disconnected and did an iCloud backup over WiFi. Not the best, but got it done. Then did the update to the iPadOS. Once it was updated, I tried again to connect to the MBP and got exactly the same issue. Thought about it for a couple of minutes and had the bright thought that maybe it was overdrawing the USB port for power, even though it was fully charged. Connected a USB powered hub, connect iPad to hub. The iPad connected to Finder, stayed connected and the backup to the local drive was completed with no issue.

I'm posting this here in case anybody else has the same symptom of connect/drop and wonders what to try. Not expecting any fixes, jus found it curious and I learned something.

 

[Rod]

I tend to update the iOS/iPadOS versions on the devices these days rather than via USB to the macOS Finder.
I'll try my iPad to MBP connection as soon as it's completed the current update. Already updated macOS to 11.4
PS, I'm sure you tried changing the cable?

 

[chscag]

Most iPads draw too much current to be charged from a MacBook Pro. Even my iMac which provides more power from its USB-C port will not charge my 10.5" iPad Pro.

I can attach it to the iMac and it will show up in the Finder and stay connected but won't charge. I have to charge it separately.

 

[ferrarr]

That's the same issue I have, when I use cords that didn't come with my 1st gen 12.9" iPad Pro. I never had that issue with the cable that came with it.

 

[MacInWin]

I didn't intend to make a discussion of this. I had just not expected it. The iPad was at 100% charged, so I thought it would not strain the USB port. I know iPads draw more power than the USB can handle, but in the past that just resulted in a data-only connection. The iPad would charge if the screen were off, but as soon as the screen came on, the charging would stop. But it would still do the data connection for backup/installations, etc. Now the behavior is different in that the entire port stops operating. Don't know when the change occurred, but it is different now. Different cables, different ports on the MBP didn't matter. I figured a workaround with the powered hub, just wanted to document it in case someone else sees the behavior and is looking for a solution.