Model number: WD10EZEX-07ZF5A0 (Western Digital 1TB Blue)
Date of manufacture: November 2013
The hard disk drive was from inside a desktop computer belonging to a German multinational engineering and electronics conglomerate company who have premises based in Greater Manchester. The HDD had not sustained any physical shock before failure. The work was requested on the ‘priority service’ and was completed and return within 3 working days of receipt.
Hard disk drive symptoms:
The owner reported that Windows would partially boot, but would hang or restart. Moreover, he reported that the HDD made a distinctive buzzing noise. Removing the HDD from the computer and attaching it to a USB docking station would not allow access to either of the two partitions.
On receipt the HDD would initialise and reach a ‘ready’ state. However, this would take longer than is typical. There was no obvious buzzing noise, but a complete initialisation of the motor did not occur on the first attempt of the HDD’s initialisation process.
On successful initialisation the read-write heads, PCB, and firmware were tested. There appeared to be relatively normal functionality in each of these. Read attempts were made to a number of LBA values (sectors). Data could be read OK but with some read-errors (bad sectors). The HDD was configured for disk imaging on a hardware disk imaging equipment. During disk imaging the HDD made a progressively louder buzzing noise with a high level of read-errors. The noise was omitted from the spindle motor. When the HDD was powered off, and then on, the noise would continue. Tests revealed that the noise (and resistance in the spindle motor) was affected by the operating temperature of the HDD. As there was an increase in operating temperature there was an increased resistance in the motor bearing, causing a high number of read errors.
The HDD temperature was controlled and lowed. Disk imaging continued until completion with a second and third pass required to read all important sectors. A full recovery of the critical data was made.
This fault in the spindle motor is not frequently seen in Western Digital hard disk drives. CDR will be assessing other WD10EZEX disks for similar symptoms of failure.
The HDD was under a manufacturer warranty and the customer requested the failed HDD to be returned. Consequently it was not possible to open the HDD and assess the physical condition of the motor bearing once recovery was completed.