External Drive keeps disconnecting
Mac Mini 2010, Mac OS X (10.6.4)
Mac Mini 2010, Mac OS X (10.6.4)
I might be a years late but seems people still asking. This is probably a power problem. I ran mac OS X with no problem from a Samsung evo ssd inside a non powered enclosure. Tried upgrading to mac sierra via the external then it always disconnected. I managed to find a way around by copying over files. But once upgraded if doing processor intensive actions like compiling code or installing apps the machine would freeze and die. I noticed it was the drive stopping I install keep drive spinning app. Didn't help. I waited until high sierra for a patch. Then I randomly found here that mac OS' (any version) will disconnect your USB device if it's drawing too much power https://discussions.apple.com/thread/3739129?start=15
A USB 3.0 can only deliver 0.9A a good hard drive would draw more than this, in my case 1.4A. I changed the enclosure to one with external 5V DC power input jack (USB to jack cable costs
You can see this in system profiler, I'm not sure why Apple can't build this protection/logging into the OS, it seems it already detects a low amp and disconnects problem anyway.
I got this issue after updating my Mac Mini to Sierra 10.12.6. Before that no problems with my 4 connect external HD's. Now 2 of them drop their connection every day.
Those two are of the same brand connected via USB 3 port. In system info it says via the ASMT 1053.
One other WD HD stays connected, it says in sys info under USB 3 Bus via Ext HDD1021...
The one connected via thunderbolt also stays connected.
Who is the culprit?
This issue is still present in 10.6.8 after applying the Combo update. Can any Lion beta testers confirm whether it appears to be fixed in 10.7?
gperetz wrote:
This issue is still present in 10.6.8 after applying the Combo update. Can any Lion beta testers confirm whether it appears to be fixed in 10.7?
If there are any beta testers, they are bound by an NDA (Non Disclosure Agreement); so you will not get an answer to that question: either we don't know or aren't allowed to discuss it.
Problem is still there for me I'm afraid.
I've got the same problem occuring with two different external drives, and it doesn't seem to matter what the connection method is either. I can connect either drive via USB2 or FW800 and the same issue occurs. It will disconnect randomly.
I've considered getting another new drive just for backups but at the moment I can't have any confidence that it will actually connect so I'm rather stuck as to what to do..
Same problem here. The problem is only with FireWire drives. USB drive works fine. I am using Lion.
Seagate GoFlex 1TB connected with FW800 to my Mac Mini (Lion), no disconnects here. But on bootup, the drive sometimes seem to lack power and doesen't start correctly. Have to disconnect and reconnect the cable to get it started.
External Drive keeps disconnecting