iPhone keeps disconnecting from Mac

3 apple leads used - 1 came with my 7+ im trying to use - on 11.2 beta

macbook air 2015 - plugged into mains, using battery - on high Sierra beta

reset all settings on phone

reset phone and mac

cleaned ports and leads

nothing works!!!

all other usb devices work though!!

all i want to do is back my pictures up on photos on my MacBook

I have tested this on two different MacBook Pro (mid 2015) one with Sierra and one with High Sierra. We have tested with four different cables and one iPhone 6s and one iPhone 7 Plus. One is on iOS 10.x and the other on 11.2. Still the same issue. No issues if you use the power cord.

I have a 2015 MBP. I have windows installed on my Macbook too, so I switched to Windows to see if the problem occurs there as well. But on windows the connection was fine, so i knew it wasn't a hardware problem - it had to be the fault of OSX. So I tried every single one of the advices i found on the internet and nothing worked for me.

Then I tried AndyAsb's idea - and it totally fixed for me too! (thanks so much Andy! 😀)

You can just plug in basically anything that gets power from usb to the other ports while your iphone is connected to one and this will fix your problem (hopefully).

It is a so simple solution that i have not thought about it, but the most infuriating thing is that apple made such a ridiculous mistake that they could probably fix in a small update.

I think the problem is that the os can not supply the right amount of power (too much/not enough(?)) via usb, and the consumption of more than one devices kinda "balances out" this inequality.

Hey there!

I had also this problem.. I tried everything whats written there.. nothing helped me.. I have 3 cables. 1 from Aliexpress, 1 from old iPhone 5 and 1 from iPhone 7. Right now I have MacBook Air and iPhone 7... I Had to use the cable right from the box of the iPhone 7.

sooo this is the way how to do it.

Use the cable, which you got with your phone you want to connect.

This is such an annoying problem. This should just work - it is something that is one of the most basic operations in the Apple ecosystem. You sync your idevice to your Mac. I think Apple has really lost its groove. None of the solutions here are real solutions - no on pe has identified definitely what the problem actualply is. There is a real problem and Apple needs to fix it - not make their users try things at random and hope something might seem to work. if I wanted to waste my time like that I would use Windows.

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 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.

I have MacBook Air 2017 with macOS High Sierra installed, having this issue with only my SE, 5s has no issue. I am on iOS 11.2.6 (latest in current time of writing). Mostly, iPhone SE connects and disconnects rapidly, and sometimes by mistake haha, the USB gives no issue, it happens with both the USB slots, and tried 2 Apple original cables and 1 from amazon basics. Still facing the problem. However, my iPhone SE connects smoothly to MacBook Pro (late 2012). Now i am confused, the question is, is there a problem with my Air or with my SE.

I took my mid-2015 MBP into Genius Bar under extended Apple Care for battery replacement, and they are also going to troubleshoot the USB iPhone / iPad issue. They said they are going to do an "EFI stress test" or something. I'll update upon repair completion.

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.

I know this does not make any sense, but i tried 5 different ORIGINAL cables and none worked in any of the 2 USB ports. I then tried another brand of cable (acker) I stretch it all the way and once it connected i DID NOT MOVED IT until it was done. And it worked !!! So like I said it does not make any sense at all as 2 of the OEM apple cables where brand new and just got them out of the iPhone box and had NEVER been used before. So the only advice I can give you is: try all different ways of fixing it and don't give up too quick, maybe (only maybe) you will be able to do it.

Had same problem on Late 2017 MBP ;

Little backdoor for your problem.

When nothing connected to Mac . I open VM (parallel) and run windows. when microsoft win. fully lunch you can plug your USB device or idevice; when its connected to VM; you can now shutdown Virtual Machine. Ones its shutdown your USB device keeps connected to your Mac.

ha! this solution worked for me too! but how weird is it??!! there must be an issue with the USB port or cable... but you say it only happens with your iPad and not your other devices. sounds like something apple needs to address...

Reset the SMC > Intel-based Macs: Resetting the System Management Controller (SMC)

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