Sony PS2 drives should respond to Maxtor's diagnostic tool (don't remember the name of it).
First verify your HDD isn't actually bad. It MUST be a legit, factory-pressed disc PS2 drives won't accept a burned disc without some trickery and the disc boots in a special way that prevents us from using that trickery. This will be a pressed CD or DVD that the PS2 will recognize. You can resurrect this machine IF you have:
(Again, private forum can't link.) This is a common issue caused by a bug in the bootloader on the HDD, corrupting itself. I've been reading through the thread I mentioned earlier.