USB Drive Ejection and Activity LED on Mac


macrumors regular
Original poster
Oct 31, 2003
Greetings all, :)

I own several SanDisk USB flash drives which all exhibit a strange type of mac incompatibility (tested drives: 256 Cruzer, 512 Cruzer Micro with blue light, 1GB Cruzer micro with retractable USB connector with U3, and one with U3 removed no difference). When I eject the disk from the finder the drive sucessfully unmounts however the light on the drive remains on. Removing the drive always makes me a bit nervous as it is difficult to ascertain if the computer is done with the disk. On more than one occasion I apparently did not wait long enough and got a USB device removal error (you know data may have been lost or corrupted...). On a PC all of these drives turn off the LED after being ejected. I suspect that this is a SanDisk issue as I have a very old 128MB Linksys USB flash drive that indeed turns the LED off after ejection in OS X.

Since I am in the market for a new drive I would appreciate member comments on what USB drive they own and if the light turns off after ejecting the disk in OS X. In particular I wonder if anyone has experience with the Imation USB drives with the swiveling connector cover. This drive is on sale a Target this week. :)


Moderator emeritus
Apr 27, 2005
San Francisco, CA
I have both a Sony MicroVault Flashdrive and a PNY Attache Flashdrive and neither exibit that behavior.

I don't believe it really matters with flashdrives though.


macrumors 601
Mar 20, 2005
Are you sure it's just not a difference between ejecting a disk in OS X and stopping a USB device in Windows?

When you eject the drive in OS X, it is still being powered, but data is cut off to prevent loss when unplugged. Therefore, because there's power, the light remains on.

On Windows, maybe stopping the USB device cuts power and data, therefore putting the light out altogether.

Not sure....just a theory!

Fleetwood Mac

macrumors 65816
Apr 27, 2006
Don't worry about it. I have a 512 cruizer. It does the same thing, and I've been using it with various Macs for about a year. Not a problem yet.


macrumors 65816
Jul 29, 2005
Don't step into the kawoosh...
I had the problem with a light not turning off when i unmounted a drive. It was a cheap supermedia store drive. I ended up sending it back becasue the thing would not stop corrupting data or not coping stuff right.

I returned it and got a Lexar 2GB drive. Works like a charm and have not had a problem with it.


macrumors regular
Original poster
Oct 31, 2003
Thank you all for the replies. :) I guess I am prepared to call this a SanDisk issue and move on to another manufacturer. It's really a shame as SanDisk is the only place you can get a 1GB drive for 15 bucks. In the same manner as iDuck, I personally have not had reliability problems with the drives, but my wife has had two die on her and the LED issue continues to maker her nervous. Even after removing U3 with their own program I still have other issues with the newest of my SanDisk drives. I had also considered a data vs. power difference for disconnecting USB devices in Windows when compared to OS X as suggested by ITASOR, however it does not seem as likely other USB flash drives and also devices such HDs power down just fine. It is great to hear that USB drives from other manufacturers work properly and so I'm headed away from SanDisk. :)


macrumors regular
Feb 18, 2008
go to sleep

Well this issue is right up my alley, I was looking into the same problem and what Apple does is indeed to leave the power on but to cut the flow of data and thus the light remains lit. I had a friend who I thinky had a PNY flash hdd drive and the light went out but cannot comment too much on that.

Still, the reason for the power to remain is for devices such as the iPod to charge when disconected from iTunes.

The final post briefly mentioned the iDuck USB which is a beautiful little USB memory stick shaped as a duck and with an internal light flashing. On Windows XP (not Vista; the light stays on -- they caught on) the duck light went out and it make the whole process quite emotional.

I am looking for a script or a program that will give me access to the USB power settings in Mac so I can make my little ducky go to sleep. Anybody know?