Samsung MP0402H spin up and down

[stoney1981]

Hi all i have a Samsung MP0402H that spins up and spins down. I know this is caused by a pcb. I have tried 3pcbs that i know to work. However my hdd appears to be breaking the pcbs giving them the same problem. Does anyone know what causes the pcb to go like this. Thank you all for your time.

[rchadwick]

Shorted Preamp?

[rameez]

In some cases overflow of ALIST causes the same issue .

[N.C.]

This happens, is the firmware part are incompatible the other parts on the platter.
The fw part on the pcb side, sometimes is burned into the mcu chip.

Or can be something else, like Alist issue...

Janos