The failure of this drive surprised me, because it's not even four years old and it's only been used intermittently (maybe an hour per day on average).

The drive gives off a quick series of very quiet clicks (for about three seconds), a quick whine, and the same series of clicks again. Then it shuts down without ever spinning up the motor.

Opening the drive reveals nothing: No surface damage, heads are parked properly, both spindles and heads can be easily moved. Spindles twitch slightly during the click sequence, but nudging them by hand doesn't do anything either.

The mainboard doesn't show any damage. Zero-Ohm-resistors are fine, TVS diodes are blocking in one direction and show a voltage drop of 0.5V in the opposite direction.

Measuring the motor pins sequentially gives me 3x 0.8 Ohms and 1x 1.7 Ohms.

Changing the power supply gives me the same issue.

Isolating the preamps gives me the same issue.

Isolating the motor pins makes the startup attempt completely silent.

I suspected that the motor controller caps went dry and soldered an electrolytic cap to the 5V-tantalum caps next to the motor controller. Nothing.

What could possibly be wrong with this thing? I don't care enough about the data to try a PCB replacement, but I'm really baffled what I'm missing here.

Seems head Failure.....

Any way to confirm that? I bought the same drive again and would hate to get the same error again after 4 years. Most of my drives are still functional after 8-12 years.

there is no way to ensure it will work the next week...
U need backup.

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Adatmentés - Data recovery

I have a great backup, but I'd rather not buy a $100 drive every four years if I can prevent it.

Buying better quality drives may help. Green WD series is known for bad sectors and bad heads within 1-2 years of use. Also, the trend is for manufacturers to build drives for specific purposes. So, a particular drive (according to its design) may matter in how it is used. For example, Green Series is considered a "good for long term storage with the occasional use".

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Hard Disk Drive (HDD), Solid State Drive (SSD, SATA, NVMe, etc), USB Flash Drive and RAID Data Recovery Specialist in Massachusetts