determining if hdd head electronics is ok?

[anglomont]

Need to try replacing the damaged drive pcb and would like to find out
if electronics inside the drive (head preamps etc..) are ok to avoid
the possibility of burning the good pcb.How likely is this to happen if
the drive was invisible by bios and would not spin with it's damaged
pcb ?Any good trick -perhaps monitoring the heating with a thumb on
motor controller chip or using an ohm-meter to check for shorted pins
going inside the drive?

 

[Rod Speed]

Need to try replacing the damaged drive pcb and would like
to find out if electronics inside the drive (head preamps etc..)
are ok to avoid the possibility of burning the good pcb.

They wont burn the good pcb even
if they have got fried or damaged.

How likely is this to happen if the drive was invisible
by bios and would not spin with it's damaged pcb ?

Cant happen.

Any good trick -perhaps monitoring the heating with a
thumb on motor controller chip or using an ohm-meter
to check for shorted pins going inside the drive?

You dont get shorted pins inside the drive
and they wouldnt do any harm even if you did.

Its theoretically possible for a bad motor to kill whats
driving it on the original pcb and the replacement,
but in practice thats not seen very much at all.

You do sometimes see a situation where a board swap
between two identical brand new drives doesnt allow
either drive to work again, even with the boards swapped
back to the original drive. Not too clear what happens there,
most likey the firmware decides that its not on the original
drive and chooses to come up again, even when back on
the original drive.

 

[Arno Wagner]

Need to try replacing the damaged drive pcb and would like to find out
if electronics inside the drive (head preamps etc..) are ok to avoid
the possibility of burning the good pcb.How likely is this to happen if
the drive was invisible by bios and would not spin with it's damaged
pcb ?Any good trick -perhaps monitoring the heating with a thumb on
motor controller chip or using an ohm-meter to check for shorted pins
going inside the drive?

Basically you need the drive's shcmatics and check the preamp.
However, while possible, the preamp is a low-power circuit and
has a low probability of damaging things, unless completely
fused. There is no electronics in the motor.

You will have to risk it. This is advanced technology, doing it
safe and on the cheap is not possible.

Arno