HDD GURU FORUMS

Hi all,
I'm looking for NVRAM for those drives. I've got 3 of them and all suffers from same, trying to start but only makes only bzz bzz for few times. Then motor driver IC is getting hot. I'm assuming corrupted firmware.
Are those drive can be talked to with telnet RX/TX, I've tryied like with Seagate but got nothing on telnet.

Pretty sure the ALA family still isn't supported by SD.

And what about trying to rewrite NVRAM only in chip programmer, if I could get NVRAM from working PCB ?

If you read the manual if you can understand it there is a way to start non supported drives in SD tools. but if your MCU is hot this can be another issue from the buzz buzz buzz

Motor driver gets warm after 2 first attempts of powering hdd.
More tries, the more warm it becomes.
Removed PCB is not getting warm. It looks like those bzz bzz sound is getting from
HEADS coils. Like it was trying to power on motor's but can't, and after few tries it stops.
So that's why I'm thinking about firmware issue.
If I would have a working donor PCB it would be easier.

P.S. I've disassembled one hdd and heads are OK parked on plastic park zone, moving with ease, also hdd motor turns with ease, so this is not a stucked bearing.

woxy wrote:Motor driver gets warm after 2 first attempts of powering hdd.
More tries, the more warm it becomes.
Removed PCB is not getting warm. It looks like those bzz bzz sound is getting from
HEADS coils.

If you want to eliminate the "heads coils", then place some insulation tape over the VCM contacts.

Otherwise, did you measure the resistances of the motor windings?

fzabkar wrote:If you want to eliminate the "heads coils", then place some insulation tape over the VCM contacts.

I've tryied to insulate from VCM contacts, by unscrewing PCB. I've also tryied just to connect
motor contacts to PCB, no result. The part of bzzz sound is missing some bzzz, but it is only bzz.
I've found some old ATA Hitachi hdd (working drive). Was trying to spin 2TB from old Hitachi PCB,
only bzzz sound. But old Hitachi on its own PCB just connected to motor, spins nicely.
Could it be motor, even if it rotates without any resistance?

fzabkar wrote:Otherwise, did you measure the resistances of the motor windings?

I haven't checked it yet. How to check it? As I can see all motor windings are connected, so I need to unsolder
it to measure, am I right?

saxleo wrote:Pretty sure the ALA family still isn't supported by SD.

Correct. Although the Hitachi DR was recently updated with stuff nobody uses.

@woxy, you say that you were not able to spin up the 2TB drive using the PCB from an old Hitachi HDD. Did you try spinning up the old HDD using the 2TB PCB?

As for measuring the motor windings, just disconnect the PCB, locate the solder points on the motor's hub, and then measure the resistances between the common terminal and each of the three windings, or measure the resistances between each pair of windings. There is no need to desolder anything.

fzabkar wrote:@woxy, you say that you were not able to spin up the 2TB drive using the PCB from an old Hitachi HDD. Did you try spinning up the old HDD using the 2TB PCB?

As for measuring the motor windings, just disconnect the PCB, locate the solder points on the motor's hub, and then measure the resistances between the common terminal and each of the three windings, or measure the resistances between each pair of windings. There is no need to desolder anything.

I've tried both ways:
old Hitachi PCB to new Hitachi - bzzz bzzz
new Hitachi PCB to old Hitachi hdd - something similiar to bzz bzz

Will measure motor windings as soon as possible.
One more thing, is this in all hdd's that they spin up just on motor connectors, without heads connector?
Or it depends on drive manufacturer? I'm asking, because as I can remember the recent Seagate 7200.11, I've been detaching heads connector to be able to talk with hdd via rx/tx terminal, hdd was spinning up for a couple of seconds, then it spinned down.
The old Hitachi hdd spins up also only on motor connector.

thatdellguy wrote:

saxleo wrote:Pretty sure the ALA family still isn't supported by SD.

Correct. Although the Hitachi DR was recently updated with stuff nobody uses.

How True How True ,

Those guys did not give us the drives support that we needed boooooooooo

woxy wrote:One more thing, is this in all hdd's that they spin up just on motor connectors, without heads connector?
Or it depends on drive manufacturer?

ISTR (from other threads, not personal experience) that certain WD models won't spin up if they can't detect a preamp. FWIW, if I were investigating this behaviour (in the WD drive), I would isolate the I2C clock and data signals to see if they were responsible for the no-spin condition. Otherwise, it could be that the FAULT pin defaults to TRUE when the preamp connector is isolated. But that's only speculation.

As for your Hitachi drives, have you measured the voltages at the motor terminals?

fzabkar wrote:As for your Hitachi drives, have you measured the voltages at the motor terminals?

Yes I've had. Connected to the sata power connector, measuring between pcb GND and motor pins:
1 pin - between 4.89V - 3.3V - voltage goes up, and when bzz sound appears it goes down
2 pin - something like 3.3V - and something lower - voltage goes up, and when bzz sound appears it goes down
3 pin - something like 3.3V - and something lower - voltage goes up, and when bzz sound appears it goes down
4 pin - as I recall no voltage

but those info I will have to confirm later today, will measure one again.

woxy wrote:but those info I will have to confirm later today, will measure one again.

Measured and looks like this:
1. An old Hitachi has 6.03V on all 4 motor pins during work (spinning)
2. New 2TB Hitachi has:
1 pin - between 4.89V - 3.3V - voltage goes up, and when bzz sound appears it goes down
2 pin - something like 3.3V - and something lower - voltage goes up, and when bzz sound appears it goes down
3 pin - something like 3.3V - and something lower - voltage goes up, and when bzz sound appears it goes down
4 pin - between 4.89V - 3.3V - voltage goes up, and when bzz sound appears it goes down

In 2TB Hitachi, when PCB is disconnected from motor pins, voltages on all 4 pins are floating up to 3.47V, and then I can hear click near heads (no bzz when motor disconnected).

fzabkar wrote:As for measuring the motor windings, just disconnect the PCB, locate the solder points on the motor's hub, and then measure the resistances between the common terminal and each of the three windings, or measure the resistances between each pair of windings.

Checked resistance on old Hitachi and new Hitachi, looks the same, about 0.6 Ohm on each winding.

Your 2TB PCB appears to be trying to spin the 2TB drive, but it can't spin the "old" drive. This would suggest that the 2TB board is bad. Since there is activity at the motor terminals, and since the motor controller is warm, this would suggest that the PCB firmware is good, and that the fault is somewhere in the vicinity of the motor controller.

OTOH, your good "old" PCB is unable to spin the 2TB HDD, so this would suggest that the 2TB motor is faulty, or that there is a stiction fault or a seized bearing. Yet you have confirmed that the motor spins easily by hand, and that its windings are electrically OK, at least on a multimeter.

The unlikely conclusion appears to be that all three 2TB PCBs and all three 2TB motors are bad.

I confess that I don't understand.

One more thing I would try is to measure the motor current. There should be a current sense resistor or resistor array whose voltage will be proportional to the motor current. If you could upload a photo of your PCB, I may be able to help you locate these resistors.

Here are PCB images:





Also, I've tried one more thing. 2TB PCB on 2TB HDD with heads connected,
but with connected old Hitachi hdd motor. Same bzzz bzzz thing.

I've couldn't measure the current, because it seems that all motor coils
has to be connected. With disconnected motor, when measuring one coil
there is no current, or maybe I need to measure in some other points?

And some another idea, maybe there is some hdd heads electrical blocking mechanism, which is failing,
and that's why there can be heard bzz bzz noise? The PCB tries to unlock heads lock mechanism,
it fails to do that, that's why PCB bzz bzz only few times and stops, probably to avoid over-current?

It's just and idea, because as I've disassembled one 2TB, I've found some plastic thing near heads, that
looked like it was some kind of heads blocking mechanism. After I've released heads by hand and connected
power to PCB, heads instantly parked on theirs parking ramp.

Some new info.
I've got an old ATA IBM Deskstar working hdd.
I was able to spin up IBM hdd motor with all Hitachi 2TB PCB's.
The IBM motor spin up looked like this:
bzzzzzzzz - spin up - spin down after 3 seconds.

So then I've tried to spin up an old Hitachi hdd motor with IBM PCB,
same bzzz bzzz thing as in 2TB Hitachi with original PCB, and motor driver
on PCB was getting warmer on each bzzz.

So probably 2TB Hitachi motors are ok, PCB's (at least as for motor powering up)
are also OK. Something tells me that the bulls eye of the 2TB problem, lays somewhere
else (a for now, don't know where yet).

It's a pity that I don't have hdd motor universal controller. I could test the motors directly,
and exclude them from suspicious list.

I confess that I don't recognise any current sense resistors, either for the voice coil or the spindle motor. They would normally be less than 1 ohm.

Clearly you have demonstrated that the 2TB PCBs are OK. I assume that you have not attempted to spin up the 2TB HDDs with the IBM PCB, so the 2TB motors would still be suspect.

That said, are you using compatible boards for your testing? One scenario that would fit the symptoms would be if your boards had different pinouts for the motor connector. For example, one could be wired as A/B/C/Common, whereas the other could be Common/B/C/A. The last thing you would want is for your motor to spin backwards.