WD30EFRX-68AX9N0 strange problem (for me)

[colanco]

when connected, the disc rotates for a few seconds then stops, then rotates again and so on.

I have had similar cases before that were solved with a change of pcb, but this particular case leaves me with no options.......

patient disc + pcb donor + patient rom ----> same result (spin up/down constantly) ------> discard pcb problems

patient disc +pcb donor + rom donor ---> same result ----> discard corrupt rom problems

Isolated head contacts ---> same result ---> would rule out preamplifier or head problems

Am I missing something??

motor damage???.... but it would be the first case I see in this series and even less when it turns (not blocked).

Has anyone ever had this happen to you? And most importantly, what was the solution??

[fzabkar]

when connected, the disc rotates for a few seconds then stops, then rotates again and so on.

Isolated head contacts ---> same result ---> would rule out preamplifier or head problems

How does a working drive behave when you isolate its HDA?

[colanco]

when connected, the disc rotates for a few seconds then stops, then rotates again and so on.

Isolated head contacts ---> same result ---> would rule out preamplifier or head problems

How does a working drive behave when you isolate its HDA?

hello fzabkar, your opinions are always welcome, thank you

I know, it doesn't make sense, but it does exactly the same thing, it turns and stops turning after a few seconds, turns again, stops again........

It's haunted!!!!!!!

[fzabkar]

It appears that the firmware is designed to spin up the drive and then check the preamp, in which case ISTM that the preamp/headstack must be faulty.

You might like to compare the resistances between ground and each of the preamp supply test points (+5V & -5V). You could also measure the voltages at the HDA contacts, eg the read channel test points (TV9 & TV10).

[colanco]

It appears that the firmware is designed to spin up the drive and then check the preamp, in which case ISTM that the preamp/headstack must be faulty.

You might like to compare the resistances between ground and each of the preamp supply test points (+5V & -5V). You could also measure the voltages at the HDA contacts, eg the read channel test points (TV9 & TV10).

In WD the usual is the opposite, first check the preamp and then spin up, that's why I discarded preamp or head problems, but as I don't believe in witches, I'll do the checks.

Thank you fzabkar

[colanco]

I would vote for damaged pre-amp / head(s).

Yes, it is most reasonable, PCB and Rom are discarded and the motor is very unlikely, there are few options,

What I don't understand is the reason for the continuous spin attempts,

[pcimage]

I would vote for damaged pre-amp / head(s).

That’s what it is.