i have a wd digital hardisk. Whenever i connect the drive to the power supply. The supply is turned off. Most probably the tvs diode is shorted. I will be uploading the pic of the pcb. Can some one identify the TV diode, fuses, 0 OHM resitor.

I can't see anything that looks like a TVS diode, but I would start by measuring the resistance between ground and each pin of Q6. I'm assuming that powering up the board on its own is enough to shut down the supply.

_________________
A backup a day keeps DR away.

If your aim is to get the data back, you can just transfer the U12 chip to another PCB of the same number and it should work.

_________________
Data Medics - Hard Drive, SSD, and RAID Data Recovery Service Company

royaldsouza1, I can’t really see any visible issue from this distance in a picture but you will really have to check resistance to each pin of Q6 as mentioned. It’ll help you determine if the diode has been permanently damaged since you’ll get a comparatively small resistance somewhere where you’ll need infinite or near infinite resistance. Also, you can compare these values with a working board if need be.

Regards,
Marcel J.