Mac doesn't recognise external hard drive

[danslecarton]

Hey guys, I was directed from another forum for help.
I have the problem that my external hard disk doesn't show up on my laptop neither in Finder nor Disk Utility. It shows up in System Information though. When I plug in the hdd it drives up but goes to sleep right after as far as I can hear.
I tried using a different USB port and cable, resetting SMC and NVRAM and Solution 3 (this comes closest to my issue but I don't have any process similar to fsck_xxx running) but none helped.
My laptop is a MacBook Air mid '12 running 10.15.7 Catalina and the hdd is a WD MyBook 4TB if it's of any concern. I appreciate any help, thanks!

 

[brianmowrey]

Does the drive work connected to other machines? Assuming it doesn't sounds like the motherboard of the drive is working but the platter itself is either dead or not communicating with the board...

 

[danslecarton]

I tried to connect it to a Windows laptop but it's about the same. The disk starts spinning when plugged in but soon goes to standby or stops spinning. Does that mean that my hard drive is done and gone? That would be a shame since I need the data from there.

 

[Fishrrman]

OP:

This is a 3.5" WD drive, right?
Dumb question, but are you using the power supply with it?
Have you checked the connection where the power supply plugs into the back of the drive?

 

[danslecarton]

Haha, yes it's a 3.5" drive and it's connected to the power supply. The white LED in front is blinking indicating it's in standby.

 

[brianmowrey]

Sure sounds like a dead HD. Could be the pcb board or board-drive connection, rather than the actual platter/drive. In which cases, repair/recovery is easier. I don't think that's as likely when you are getting LEDs and initial spin-up.

I imagine what you are really after is some possible culprit outside of the drive that could be causing the same problem, though...

 

[danslecarton]

I got it running again by opening the case and replugging the controller to the hard drive. I literally just unplugged and replugged the controller. I hope it will keep on running for a few more years.

 

[pmiles]

If you have had issues with the drive... NOW is the time to look for it's replacement. You were lucky that your trick worked... what if it didn't? Hard drive recovery can be expensive if not impossible when a drive actually starts to fail or die.