Resistance gives me a 1 (in the range of miliohm) so it look like that it's damage.

Does anyone know what sort of component this is?

Thanks

I agree with sathyan, but I would also check whether there is a short between the +5V test point and ground. You might also get away with replacing the inductor with a wire link. I think it's only there to filter noise on the supply line.

_________________
A backup a day keeps DR away.

sathyan has stated that it is a chip inductor. It should have a resistance of close to zero ohms. If you are saying that your meter overranges ("1") on the megohm scale, then yes, the inductor is open circuit.

_________________
A backup a day keeps DR away.

+1

After soldering the chip inductor at both sides, the PCB was working fine! The first think i did was made a copy of the disk. I wanna thank everybody for help, and the tips. Many many thanks, i was very instructive and fun to do and to investigate the next steps.

Thanks Christian

Well done,
and remember , regular backups..

Interesting. I haven't encountered any soldering related faults in chip inductors, but standard practice for technicians is to resolder the pins of all transformers and coils, eg ...

http://www.p-wholesale.com/upimg/5/119a ... rs-698.jpg

I have also seen numerous cases where the following types of inductors have cracked around the centre of the body:

http://image.made-in-china.com/2f0j00TM ... -150mH.jpg

Anyway, congratulations.

_________________
A backup a day keeps DR away.

Yes, congratulations.

My vote is that the inductor's soldering was damaged as a consequence of the same bending forces which (as we already know) cracked the solder joints on the mini-USB connector next to it - i.e. this is all the result of external forces on that connector, and not something specific to inductors.

I have same problem, solve now thank you.

Update:

The "t056" part is a PolyZen (PTC resistor + protection diode).

viewtopic.php?t=30079&p=207705#p207705

_________________
A backup a day keeps DR away.

+1 on a HM641JX Samsung but no damage to the USB connector and never dropped.

Hi, i have the same hdd with the same problem! At first instance, hdd not detected, not spining, not led light.

After resolder usb connector and the mentioned chip inductor led light turn on and hdd spin up, but not detected mass storage device neither usb interface, there is not any signal of data TX RX.

I am suspecting about smd network component connected to data D- and D+ lines in series with 2 ohm resistor to usb bridge. Please, see circled component at bottom image.

This is a black smd network component, so i am thinking in network resistors or inductors and not in capacitors. But resistance value give me around 1.5 Mega, i think this is too high, practically open.

Can somebody point what it is this component?

thanks in advance,
Oleg.

That component looks like a common mode EMI suppression choke.

High Speed USB Platform Design Guidelines:
http://www.usb.org/developers/docs/hs_usb_pdg_r1_0.pdf

BTW, if you are getting nothing from the serial terminal port, then that's another problem. Have you checked the Tx/Rx LVTTL signal levels?

_________________
A backup a day keeps DR away.

Well, Common mode shoke in figure you shown should have continuity between in-out points (because after remove it from pcb traces are interrupted), in my case it is open, that´s why i thinking it broken, i will replace it with a 0 ohm resistor and probe.

thanks very much.