wd1501Fass reports wrong model,and different size?!-is there a way to flash/write the firmware?

@Gandusus, if you had followed up the links in the HDD Guru thread, then many of your questions would have been answered.

For example, the demo version of SeDiv will read ALL the modules, both ROM and SA. It just won’t allow you to write them. There are ways to read AND write the SA, but I know of no freeware to do this from a clickable interface. Instead you would need to write your own software, or you could write an MHDD script to do it. I could help you with the latter.

As for why the drive is reporting the wrong model number, it could be due to a damaged firmware module which itself could be the result of a bad head. However, your original description of the problem is somewhat confusing. You say that “one can create and delete partitions without problems”, which means that you can write to sector 0, yet you then say that “you can’t format them.any surface testing will fail”, which suggests that you can’t write to the drive, or at least a large part of it.

As for the model number and capacity, this information should be recorded in MOD 02. Sometimes the drive will identify itself with a factory alias (eg ROM MODEL HAWK), but this points to a different kind of firmware problem. The bogus model number is one of a long list of model numbers in a particular SA module, but I have no idea why the drive has chosen to use one of these alternatives to identify itself. Are we to assume that this is your drive, and that it spontaneously developed this fault, without any intervention on your part or on the part of others?

BTW, IDE drives sometimes report a corrupt model number, but this is most often due to a stuck data bit on the IDE interface. SATA drives don’t suffer from this problem.

Bad model number due to stuck bit in IDE interface:
http://malthus.zapto.org/viewtopic.php?f=59&t=147

According to “michael chiklis” at HDD Guru, the demo version of WDR will allow you test the drive’s heads. Hopefully this is not data destructive. I expect to receive a faulty drive in the near future, so hopefully I’ll be in a position to do my own testing.

BTW, many of the firmware modules are “dynamic”. That is, the data changes on a regular basis. Such modules include SMART, defect lists, and translator. Many failures are due to firmware corruption resulting from a damaged head’s inability to read or write these critical modules.

Here is a description of some of the modules (from WDMarvel demo version):
http://www.users.on.net/~fzabkar/temp/ModDescr_Eng.ini

Note that the function of each module may not be consistent between different models. For example, MOD 25 is listed as a SMART module, but in some drives (eg My Book Essentials) it stores the “key sector” that is needed for encryption.

In the module list you will see many references to SelfScan. SelfScan refers to a battery of factory tests that are used to calibrate the drive and to determine its defect lists and its optimal head/preamp characteristics. If your drive has a bad head, then you can sometimes recertify it as fully functional model by running a SelfScan against it and disabling the bad head. The drive will then get a new model number and a reduced capacity.