Apple keyboard needs external power

[Sangoma]

My Apple keyboard does not work with OSX if plugged directly into my iMac (late 2013). However, if I plug it into a powered USB hub, then it works.

Oddly, when I boot from Windows (Bootcamp), I can only use the keyboard plugged directly into the iMac. I don't know if this is a driver issue - it is a USB 3.0 hub.

Can anybody help with what is going on?

 

[maflynn]

Have you tried a different keyboard? Sounds like something isn't right and my knee jerk reaction is that its a hardware issue (either the USB or the keyboard).

Saying that, it is odd that the keyboard connected directly to the iMac works but not on OS X. Did you try backing up your system and doing a clean install?

 

[Sangoma]

It looks like the USB hub might be faulty - simply re-powering it made it work again.

On the other hand I have found a handful of reports that talk about the Apple keyboard not being powered properly from the iMac. What is interesting is that at boot-time it works, but once OSX (macOS) is running it is not.

If I get some time I will try a reinstall.

 

[phrehdd]

I think there are some missing pieces of info here. Is that USB HUB plugged in at the same time as your keyboard when the keyboard fails? If yes, then try taking the USB hub off line and unplug it then try the keyboard directly into the iMac. After that (if not success) reboot the iMac with the keyboard attached and no USB hub attached. Assuming it works, then* possibly consider trying to add the hub on to your iMac. Did your USB hub come with any software to install?

 

[Sangoma]

I think there are some missing pieces of info here. Is that USB HUB plugged in at the same time as your keyboard when the keyboard fails? If yes, then try taking the USB hub off line and unplug it then try the keyboard directly into the iMac. After that (if not success) reboot the iMac with the keyboard attached and no USB hub attached. Assuming it works, then* possibly consider trying to add the hub on to your iMac. Did your USB hub come with any software to install?

Thanks - I have tried with just the keyboard installed. Same problem.

The USB hub did not come with software to install it

 

[phrehdd]

Thanks - I have tried with just the keyboard installed. Same problem.

The USB hub did not come with software to install it

Did you try to reboot the system with just the keyboard directly connected and not the USB hub? Also, did you try a different USB port (maybe the same one your USB Hub was connected to on the iMac).