OK, so I've got my nightmare of the month case here. Just to quickly recap what's been done.
4TB WD Red drive had a blown motor chip on the PCB. Customer tried replacing the PCB themselves with new one and ROM transfer (cooking new PCB in the process, but didn't harm ROM thankfully). This lead to some confusion about which ROM was which, but got that all straightened out after the first day.
Heads tested with good PCB and correct ROM and found to be bad (at least I'm pretty sure they were bad, couldn't even read SPT with ldr and dir upload). Replaced heads from donor, that seems to have gone well from what I can tell.
Now, I'm finding that the SA is also a mess. When powered on the drive clicks and spins down. However after ldr and dir upload, disabling head 1 in RAM, soft reset, I can finally get SA access to the drive. All tracks and modules have been backed up by composite and check out.
However on each individual head, there's bad modules.
Head 0 has bad modules 01, 02, 32 (go figure)
Head 1 has bad modules 01, 32, 33
I've managed to force the drive to ID and even have sector access a few times, but the instant it hits a bad sector it goes right back to clicking and spinning down.
Normally I'd just plan to do a smart hot swap in a case like this, but with both copies of module 01 unreadable (except by composite) it'll just crash out a million times and I'll have to keep swapping again and again through 4TB of data. Will take forever.
So here's my question: Has anyone ever successfully relocated module 01 (The Directory Module)? I assume this is what the SA regions editing is for, but I'm at a loss as to how one would go about doing this. Would you just move the SA region then write SA tracks back over it?
Ideas?
4TB WD Red drive had a blown motor chip on the PCB. Customer tried replacing the PCB themselves with new one and ROM transfer (cooking new PCB in the process, but didn't harm ROM thankfully). This lead to some confusion about which ROM was which, but got that all straightened out after the first day.
Heads tested with good PCB and correct ROM and found to be bad (at least I'm pretty sure they were bad, couldn't even read SPT with ldr and dir upload). Replaced heads from donor, that seems to have gone well from what I can tell.
Now, I'm finding that the SA is also a mess. When powered on the drive clicks and spins down. However after ldr and dir upload, disabling head 1 in RAM, soft reset, I can finally get SA access to the drive. All tracks and modules have been backed up by composite and check out.
However on each individual head, there's bad modules.
Head 0 has bad modules 01, 02, 32 (go figure)
Head 1 has bad modules 01, 32, 33
I've managed to force the drive to ID and even have sector access a few times, but the instant it hits a bad sector it goes right back to clicking and spinning down.
Normally I'd just plan to do a smart hot swap in a case like this, but with both copies of module 01 unreadable (except by composite) it'll just crash out a million times and I'll have to keep swapping again and again through 4TB of data. Will take forever.
So here's my question: Has anyone ever successfully relocated module 01 (The Directory Module)? I assume this is what the SA regions editing is for, but I'm at a loss as to how one would go about doing this. Would you just move the SA region then write SA tracks back over it?
Ideas?
