USB ports have no power

It first started happening on my Late 2012 model iMac 21.5" a couple weeks ago.
What I found was that nothing seemed to work when connected directly to the iMac's USB ports. However, if you attach an externally powered USB hub, then all devices attached to the hub will work. So, it seems as if the USB ports are still working, but without power.
After I was able to get my USB keyboard to work using the powered hub, I was able to zap the PRAM by holding command-option-P-R while powering on, and then magically everything was back to working again. Unfortunately, this was short lived as the problem has resufaced again for me.
Has anyone else seen a problem like this? Do I need to send it back to Apple for warranty repair?

Call AppleCare & tell them exactly what you stated in your post.

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Mac Pro USB ports constantly losing power!

Hi,
Ive been looking through this forums but I havent been able to find a solution to my problem.
Ive got a 2008 Mac Pro and recently Ive been experiencing some issues with its USB ports.
The front usb ports have a USB antenna connected and some time later, it just loses power and I have to disconnect it and connect it in order to make it work again. Besides that, Ive got a USB hub connected in one of the back ports. In it, is my camera and my keyboard. After some time, it just loses power. Not at the same time than the usb antenna, but in less that an hour I have to repeat the process 2-3 times.
Worth to note, that in the two back usb ports left, Ive got an external hard drive in each and I dont have problems, there are always seen in the finder.
Some help would be great
Thanks in advance

Im running latest snow leopard.
I gave up and just used a cable for internet and a bluetooth keyboard.
I couldnt figure out why the usb antenna loses power. Though it still has a blue light linking.
What has been happening to you???

Will the PB G4 USB-ports provide sufficient power for external HDD ?

I am in the market for a 2,5in external HDD, preferably powered through the USB-ports of my PB G4. However, I have read that in many cases, Apple's laptops provide insufficient power for such devices. Is this a fact?
The drive I'm currently looking at: Western Digital Passport 120GB USB2.0 (WD Passport WDXML1200UE)

Dear Thosen, yep this can be a problem with the 12' models, I think that there are adaptors, that use both USB ports, one of power and one for data transfer. The other option is to try a firewire drive - this has the added advantage of being bootable.
bw
Andrew Platt

Which iMac usb port is high power?

Which iMac USB port is high power?

I'm not sure this is the case, at least on the newer iMacs. Some ports will adequately power some devices (most notable the USB Suerdrive) while others won't. Or, this has been the case recently, anyway; USB with Apple devices seems hopelessly arcane anyway, which makes no sense at all!)

I have a mac book pro that both USB ports have stopped working one about a year ago and one recently. Is it possible to connect to another one of the other MBP's ports with a cord that ends with a USB port?

I have a mac book pro that both USB ports have stopped working one about a year ago and one recently. Is it possible to connect to another one of the other MBP's ports with a cord that ends with a USB port?

Thank you For your time and thoughts!
I went by the Apple Store and they told me that there was a "Flat Rate" repair service for this particular part where they would replace the logic board along with the USB ports for $350. Seems like best avenue. All of this would have been moot but my wifi in the computer also doesn't work so I was using my phone as a hot spot and tethering it to the computer for Internet access when the last port quit. This left me with no internet and no printing capabilities on the computer I use for my business. Basically became a nice paperweight. lol
They will ship it off Monday and I should have it back Thursday!
Again, thank you!

Satellite C50-A-138 - All USB ports have failed

Hi
I am having a major issue with my Satellite C50-A-138.
The card reader has never worked, and one by one the USB ports have one by one stopped working.
I can connect my phone to all of them, and it will charge.
But I can't plug any device into the ports and have the laptop recognise them at all.
So far I have tried the following;
Disabling and enabling each port
Uninstalling and reinstalling
Checking for updates
Refreshing windows 8
Reinstalling windows 8
Regedit HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Contro l\UsbFlags
Regedit HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Servic es\usbhub
Downloading hotfix
Is there anything else that I can do to make them work again?

>...I did a full reinstall without settings
What do you mean without settings?
Anyway, try please to install some drive manually just to see if this will help.
- Chipset Utility
- Storage driver
- Card Reader Controller

USB ports have power but no data connection

Hello I have a HDX 16-1040 US HP, PORTS
External Ports
* 5-in-1 integrated Digital Media Reader for Secure Digital cards, MultiMedia cards, Memory Stick, Memory Stick Pro, or xD Picture cards
* 4 Universal Serial Bus USB 2.0
* 1 VGA (15-pin)
* 1 HDMI
* 1 eSATA
* 1 RJ -45 (LAN)
* 2 headphone-out
* 1 microphone-in
* 1 notebook expansion port 3
* 1 IEEE 1394 Firewire (4-pin)
* 1 Consumer IR
Product Number FS005UA#ABA
Microprocessor 2.26 GHz Intel Centrino 2 Processor Technology featuring Intel Core 2 Duo Processor P8400
Microprocessor Cache 3 MB L2 Cache
I have tried the following flashing the bios, changing power plan to not control usb power. I REALLY NEED USB PORTS PLEASE HELP ME MICROSOFT I LOVE WINDOWS 7
EDIT: the power on the usb ports work but data transfer does not.

The issue can be caused by the USB controllers. Please follow the steps below to reload USB controllers.
1. Click "Start", type in Device Manager the Search bar and press "Enter". Click Continue if necessary.
2. In Device Manager, double click to expand "Universal Serial Bus controllers", right click on the "Host Controller", click "Uninstall" and click "OK".
3. Repeat the step 2 to uninstall all items under "Universal Serial Bus controllers".
Then, restart your computer and Windows will reinstall all USB controllers automatically.
If the issue persists, I suggest that you download the latest chipset driver and BIOS from the following website, and then install then in Windows 7 RC.
Software and drivers for HP HDX X16-1040US Premium Notebook PC
Important Note: Microsoft provides third-party contact information to help you find technical support. This contact information may change without notice. Microsoft does not guarantee the accuracy of this third-party contact information.
Additionally, if you would like to restore to the OEM Windows Vista system, I recommend that you contact HP support for assistance.
Contact HP
Arthur Xie - MSFT

USB ports have stopped working on my 975 power up platinum

For some reason the usb ports on the mb & the front of the case antec p160 have stopped working, I have not added anything new or removed anything, the firewire ports are still working though. I have tried removing the usb root hub restarting the pc and letting windows reinstall the driversbut it does not make any difference. Does any one have any idea what the problem my be.

He means what is in the thread labled "If you're having problems with USB ports, read on... "
The USB issue has followed several boards. Here is a quote from a post I've made on the subjetct.
Quote from: Frankeputer
Check to see if there is a wire running from your Front USB ports to the #10 slot of your USB block which connects to the motherboard header.
USB connector block layout which corresponds to the pin layout on boards with the Intel spec for USB. Do not cut the pin on the MOBO. You are removing/cutting the wire to the connector block from the case.
2 4 6 8 10(this wire, #10, not needed)
1 3 5 7 9(filled/key)
If you find a wire leading to the #10 spot on the block, remove that wire. My block has tabs so that you can pull the wire out, or you could snip/cut the wire leading to that position--if you cut the wire, be careful to cut the correct one and cut it in such a way that it may be repaired if you make a mistake. Make sure you wrap the wire, the exposed end/s, you remove/cut with electrical tape so as not to accidentally cause a short. I actually folded the wire back and wrapped it.
2 posts to read--Here and Here.
This seems to be a common issue involving many different case manufacturers. I don't know how it applies to other MOBO manufacturers, but in these forums it is not limited to a specific MSI model or supported chipset(Intel or AMD).

My usb ports have stopped working on my iMac

2 of the 4 USB ports on my imac have stopped working. Has anyone else had the same problem? Anyone know how to get them working again?
Thanks
Pammac1

Hopefully the SMC reset works otherwise it may be a Logic Board issue.
SMC RESET
http://support.apple.com/kb/HT3964
Shut down the computer.
Unplug the computer's power cord and ALL peripherals.
Wait 15 seconds.
Attach the computers power cable.
Wait another 5 seconds and press the power button to turn on the computer.
The 5 second timing is important to a successful reset.
PRAM RESET
Zap the PRAM
Shut down the computer.
Locate the following keys on the keyboard: Command, Option, P, and R. You will need to hold these keys down simultaneously in step 4.
Turn on the computer.
Press and hold the Command-Option-P-R keys. You must press this key combination before the gray screen appears.
Hold the keys down until the computer restarts and you hear the startup sound for the second time.
Release the keys.

HP Pavilion dv6 2670qm - Windows 7 - USB ports do not power iPAD mini

All of my USB ports work fine with media drives and to connect to my Android phone.
My problem is that they don't provide power to my iPAD mini. i spent 45 minutes at the Apple store uninstalling the Apple mobile drivers and iTunes and re-installing them. The Apple tech recommended that course of action. Unfortunately it made no difference, still no power to the iPAD mini. My iPAD mini and cable work with other laptops but not my dv6 2670qm.
My iPAD mini has never worked on my laptop.
Any Suggestions?

Hi Super Mario,
Thank you for your quick reply. In the second paragraph of my post, I noted that the iPad mini and cable work with other laptops, both x86 and Apple (tested at home and the Apple store). It works for charging and iTunes on all of the other computers we have tried. Neither of those functions work on the HP dv6, in fact be iPad doesn’t even indicate that there is not enough power or that it is an incompatible port (the error messages referenced in the article). It does nothing at all when plugged into the dv6’s USB ports.
The Apple article you referenced indicates that the USB port must be at a certain power level. Can you confirm the power level for the USB ports on the dv6 Intel 2670qm? It seems like a lot of people have trouble with the USB ports on the dv6 based on the posts. Can you think of any other explanation for in the non-recognition of the iPad mini?
Thanks again.

Windows 8 USB ports have stopped functioning.

I have a Envy 1534 desktop and after taking an update to windows 8 today my keyboard and mouse no longer function past the boot system. When windows loads the keyboard goes dark and I cannot use any of the USB ports on my system. This renders the system completely useless. I have tried to go back to an earlier system point however apparently the update was already installing because as soon as i reboot it immediately reinstalls its self before i can stop it. I have not been able to access the safe mode and the refresh function fails because the "drive with my OS on it is Locked". This issue has been solved elsewhere by changing the USB mode in your bios however HP does not allow access to these bios functions. At this point I am at a loss as i cannot access windows at all, and the restore functions seem to be non functional.

Hi,
If you run into a "locked HD" situation then you will have to clear the CMOS to get the PC back to the default BIOS setting in case secure boot was enabled.
Boot up a Windows 7 or 8 installation CD and go to the command console and get MSCONFIG launched. At that point you should be able to set the boot to safe mode for the C partition on the hard drive. I just tried this process recently and it worked for me.
HP DV9700, t9300, Nvidia 8600, 4GB, Crucial C300 128GB SSD
HP Photosmart Premium C309G, HP Photosmart 6520
HP Touchpad, HP Chromebook 11
Custom i7-4770k,Z-87, 8GB, Vertex 3 SSD, Samsung EVO SSD, Corsair HX650,GTX 760
Custom i7-4790k,Z-97, 16GB, Vertex 3 SSD, Plextor M.2 SSD, Samsung EVO SSD, Corsair HX650, GTX 660TI
Windows 7/8 UEFI/Legacy mode, MBR/GPT

Could both of my USB ports have stopped working at once?

Before today, I have repeatedly connected my printer and camera to my MacBook Pro. But today nothing has worked through either USB port: not a Seagate external hard drive, not the printer, and not my camera. Could something have gone wrong with the ports all of the sudden? Can I do anything other than send it in for repair?
MacBook Pro Mac OS X (10.4.6)

Reset SMC. http://support.apple.com/kb/HT3964
Choose the method for:
"Resetting SMC on portables with a battery you should not remove on your own".
Best.

USB ports -- not enough power error

Hello, I tried to connect my blackberry phone to my Mac Powerbook, running leopard, and on the phone's screen, it warned me that there was not sufficient current or power in the USB to use it. It told me to make sure that the drivers were installed. What's wrong?
~Psych

actually issue is even worse...
usb ports don't work left and right.
yesterday they were not even turning devices on >(i.e. my cruzer 1gb disk)
today it recognizes devices ( i see them in system profiler)
but they are not seen by the system.
i tried 2 different usb keys, 2 different hd, 1 ipod 4g, nothing at all...
actually behaviour is a little bit different left to right (something is seen 1st shot on one side, after some tries from the other)
still, EVERYTHING WAS WORKING PERFECT 3 DAYS AGO!!!!
will change it for an mba
Steve: ANY HINTS????

Both USB ports have gotten extremely slow

I was hoping someone could help me with a strange problem that has come up lately. I have two external hard drives that I frequently move files around and have had no problems with speed rates via the USB ports before. I have a slightly older MacBook version 4,1 according to the System Profiler and two fairly new external hard drives, both 2TB WD Elements. I have been using these for over a year with no problem moving files around, crisp, not entirely fast but not incredibly slow either. I am updated all the way on my Macbook to 10.6.8 and I have searched Google high and low for an answer but I can't seem to find out a solution. The problem is that now where it used to take 3-5 minutes to copy over 1GB worth of files it now takes close to an hour. I have tried other USB flash drives, other external hard drives and all of them are this slow. I tried moving the same files, using a different computer, a MacBook Pro that is also 10.6.8 and the transfers are fine, same as they always were. I have tried resetting the SMC but that did not fix the problem. There seems to be very few other suggestions so I was hoping someone had an idea.
Thanks in advance for your help.

I also wanted to mention that both drives are formatted with GUID tables, one is formated as Mac OS Extended and the other is Mac OS Extended (Journaled). Both are slow when copying to each other or from the desktop to the external hard drive. Though the Journaled one seems faster when it is the only one plugged in. The vanilla Extended seems to be slow regardless of whether it is plugged in by itself on either USB port. Like I said above, this is not usual behavior, I have had no problems before a few days ago with USB speed.

Which USB port for extra power for external Superdrive?

I just bought an external USB slimline optical drive that doesn't use AC power, instead it comes with a USB Y-connector so that it can use two USB ports for power. I can't really spare the extra port. I read that the Mac mini 2011 is compatible with the Apple USB Superdrive. It does this by supplying additional power over USB, like the MacBook Air. I've tried my drive with just a single port and it powers on and can do some stuff, but suddenly it'll crap out and the OS will tell me the disk was removed without being ejected. I've determined it's a power issue. Does anyone know which port in particular the extra power is delivered through? I'd test myself, but I'm afraid I may be damaging the optical drive when it craps out.
Thanks

I'd get a good AC high powered USB Hub...
http://eshop.macsales.com/item/NewerTech/USB2HB7PRO/
http://eshop.macsales.com/item/MacAlly/TRIHUB4/
USB thing reproduce like Rabbits!

USB ports have no power

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