Hard drive won't spin. Burned TVS diode?

Socal_Tech_Dude · 10-14-2009, 01:28 AM

I have a Hitachi Travelstar 500GB 2.5" SATA drive in an external USB case. I connected the wrong power supply to the and my computer locked up. I immediately unplugged the adapter, but now the drive won't spin.

From reading other posts I've determined that the TVS diode on the logic board might be damaged. I want to try removing one end of the diode from the board, but I want to make sure I have the right component.

Can someone take a look? I think the diode is at D1 and maybe a fuse at F1.

**raptor_pa** · 10-14-2009, 05:35 AM

Is this a pic of your board or is this one from online of the same model? D1 appears to be a 5vDC Diode, and f1 does look like a fuse. Not sure about the component next to D1, it also appears to go from teh 12v trace to ground. What is the make and model of the drive, and can you post a clear pic of the same area of your drive? I haven't done a TVS fix on Hitachi. The no spins I have worked on on them have been solved with a PCB swap. You can check the diode with a multimeter set on diode check, it should read short ( tone ) in one direction and open ( no tone ) in the other. The fuse should be read on resistance scale and should be short in both directions.

Socal_Tech_Dude · 10-14-2009, 03:28 PM

That is a picture of my actual board. I took it with the macro setting on as close as could get. These are the specs:

Make: Hitachi
HDD: 5K500-500
Model: HTS545050KTA300
Date: June2008
P/N: 0A53487
MLC: DA2354
PCB: 0A55840DA2130A X14821036D

The fuse does read short in both directions and the diode has resistance in both directions. My multimeter is analog a doesn't have a diode setting.

**raptor_pa** · 10-14-2009, 05:24 PM

Diodes will read some level of resistence, usally low in one direction and higher in the other. I'm quoting from memory from a long time ago, but I believe on most meters diode check considers 'short' to be less than 100 ohms. If the resistance is low and close or high and close in both directions then there is a good chance it is the diode.

10-14-2009, 05:35 AM	#2 (permalink)
raptor_pa Mod Hardware Team Join Date: Dec 2008 Location: Central PA Posts: 4,821 OS: XP	Re: Hard drive won't spin. Burned TVS diode? Is this a pic of your board or is this one from online of the same model? D1 appears to be a 5vDC Diode, and f1 does look like a fuse. Not sure about the component next to D1, it also appears to go from teh 12v trace to ground. What is the make and model of the drive, and can you post a clear pic of the same area of your drive? I haven't done a TVS fix on Hitachi. The no spins I have worked on on them have been solved with a PCB swap. You can check the diode with a multimeter set on diode check, it should read short ( tone ) in one direction and open ( no tone ) in the other. The fuse should be read on resistance scale and should be short in both directions. __________________

10-14-2009, 03:28 PM	#3 (permalink)
Socal_Tech_Dude Registered User Join Date: Oct 2009 Posts: 2 OS: Windows XP	Re: Hard drive won't spin. Burned TVS diode? That is a picture of my actual board. I took it with the macro setting on as close as could get. These are the specs: Make: Hitachi HDD: 5K500-500 Model: HTS545050KTA300 Date: June2008 P/N: 0A53487 MLC: DA2354 PCB: 0A55840DA2130A X14821036D The fuse does read short in both directions and the diode has resistance in both directions. My multimeter is analog a doesn't have a diode setting.

10-14-2009, 05:24 PM	#4 (permalink)
raptor_pa Mod Hardware Team Join Date: Dec 2008 Location: Central PA Posts: 4,821 OS: XP	Re: Hard drive won't spin. Burned TVS diode? Diodes will read some level of resistence, usally low in one direction and higher in the other. I'm quoting from memory from a long time ago, but I believe on most meters diode check considers 'short' to be less than 100 ohms. If the resistance is low and close or high and close in both directions then there is a good chance it is the diode. __________________