iPhone keeps disconnecting from Mac

Try this: It may not work, but it worked for me and someone else. I bought a replacement charger wire for my iPhone 5s, and after trying to use it to connect to my Macbook (late 2013), it rapidly connected/disconnected.

Check the "Show Percentage" on your laptop's battery icon at the top right hand corner and then uncheck it. Hopefully this resolved the issue.

Yes this was the only thing that worked for me. I'm guessing it's because I am not using original Apple usb cord. I use a d-link 4 port usb hub and it works no problems. I spent hours before I tried this fix. I was connecting a Iphone 4 to a Windows 10 computer. However it worked fine on my other Windows 7 computer without the hub. Hope this helps.

Resetting my location and privacy did nothing, Resetting my network setting worked. It stopped the rapid connecting and disconnecting.

Hi DKMeder,

Was it the network settings on your phone that you reset or the computer and what procedure did you use? Could you also tell us what phone it was and what operating system you were connecting to?

Thanks

It was on my iPad. I went to General>Reset>Reset Network Settings. Would be the same for an iPhone too.

I have the same issue on my MacBook Air (13-inch, Mid 2013) x Iphone 6 charging.

It helps for me: Iwanted to buya new cable (not original Apple) but in the store I connectedusing the new cablethe phone to the laptopusedlatest carrier settings in itunes to the phone. it worked well. Thentried to connect the phone to mac airwith the oldoriginal Apple cableand it worked too! Idid not buya new cable 🙂.

The only thing that always solves this for me with older cables is to use an external USB hub between the iOS device and the computer. I personally believe this is a problem with non-USB-3-compliant cables when connected to USB-3 ports on Macs. I've run into similar issues on PCs where certain devices (like memory card readers) crap out when connected directly to a USB-3 port, but work fine if connected to a USB-2 hub that is, in turn, connected to the USB-3 port.

Of course if you have a newer, USB-3-compliant Lightning cable, then it works fine. For example iPad Pro comes with the beefiest lightning cable I've ever seen. Six feet long, and it's thicker and tougher-feeling than regular Lightning cables. The iPad Pro charger is also a 12-watt charger (normal iPad charger is 10-watt). USB-3 is rated to a higher amount of current than USB-2, so I suspect that what we are seeing may be related to a power issue.

If the iPad is disconnecting due to power issues, it may be disconnecting in order to protect a lower-power device from a situation where its circuitry could be overloaded and damaged. If that's the case, then the errors we're seeing are a symptom of that.

It's possible there are multiple different problems that can cause the same set of symptoms (iPad disconnects repeatedly).

What is the Apple line on this?

I had no issues on a year old iPad until 2 weeks ago and now I cant use the device as I wish.

I have tried all the hacks in this thread and had a brief moment of respite when I switched form flight mode to non flight mode.

Is there anyway to access, reset or control the Mac USB settings?

Same problem here, brand new 2015 15" MacBook Pro, connecting iPhone 6s to right USB port works, left USB port gives:

11/03/2016 23:10:27.035 iTunes[54327]: tid:93b7 - unable to query device capabilities

I've also experienced the rapid connect/disconnect charging sound from iPhone with the left port too.

I've actually found the solution!

Having tried all the ideas posted here, nothing worked, BUT my problem was instantly resolved by doing the following:

1. Go to: System Preferences -> Network -> iPhone USB (on left menu)

2. Uncheck: Disable unless needed

Voila! I assume it's to do with the instant hotspot feature, which makes sense as the logs are full of network related issues when the connect/disconnect occurs.

Apple have told me that other issues with instant hotspot (not connecting etc) are resolved in OSX 10.11.4 - haven't updated myself yet to check, but hopefully this one will be resolved in with it.

thanks dude its helped me🙂🙂🙂

It does indeed work to hold the USB cable connector up slightly at the computer end.

Nope, doesn't work for me Chrise86.. All my devices are still doing the same...

I had a similar problem where any of my devices (IP6, iPad Air 2) spastically charged from both USB ports and with any approved cable. I wanted to throw my devices out the window after hearing that **** charging sound go on and off, on and off, on and off. After a few minutes the devices would charge normally, however. Resetting the NVRAM solved this for me. I couldn't tell you why, but found it on another forum as a suggestion and it did the trick.

How to Reset NVRAM on your Mac - Apple Support

How to Reset NVRAM on your Mac

Learn about your computer's NVRAM, and when and how to reset it.

What is NVRAM?

A small amount of your computer’s memory, called “non-volatile random-access memory” or NVRAM, stores certain settings in a location that OS X can access quickly. The settings that are stored in NVRAM depend on the type of Mac you're using, and the types of devices connected to it.

Information stored in NVRAM can include:

• Speaker volume
• Screen resolution
• Startup disk selection
• Recent kernel panic information, if any

If you experience issues related to these features, you might need to reset the NVRAM on your computer. For example, if your Mac starts up from a startup disk other than the one you've specified in Startup Disk preferences, or if a question mark icon appears briefly when your Mac starts up.

Resetting NVRAM

1. Shut down your Mac.
2. Locate the following keys on the keyboard: Command (⌘), Option, P, and R.
3. Turn on your Mac.
4. Press and hold the Command-Option-P-R keys immediately after you hear the startup sound.
5. Hold these keys until the computer restarts and you hear the startup sound for a second time.
6. Release the keys.

After resetting NVRAM, you may need to reconfigure settings for speaker volume, screen resolution, startup disk selection, and time zone information.

If issues related to these features continue on a desktop Mac (like an iMac, Mac mini or Mac Pro), its logic board battery may need to be replaced. The logic board battery on desktop computers helps retain NVRAM settings when your Mac is unplugged. You can take your Mac to an Apple Store or Apple Authorized Service Provider to replace the battery on the logic board.

Learn more

On older Mac computers, similar information was stored in Parameter RAM (PRAM). Resetting NVRAM on Intel-based Macs using the same key combination is like resetting PRAM.

Power related settings can be controlled by the System Management Controller (SMC) on your Mac. If you are experiencing issues with powering on your computer, sleep, wake, charging your Mac notebook battery, or other power-related symptoms, you might need to reset the SMC instead.

Last Modified: Mar 17, 2016

Had this same problem with my new macbook and my new iPhone SE with original lightning cable.

For development, I have been using "insignia sync cable" from best buy and it works perfect. It also comes with one year warranty.

I am really happy with it and will never use apple's lightning cable to sync with my mac.