I (my father) had a lacie big disk 500 gb, it started, then the blue light came, but then it wouldn't connect to mac or pc. I putted it away as junk. Now 2 years later I picked it up again to see whether the hard disks inside were still working (yes, in my case it were 2 hard drives in some kind of raid setting (raid is making several hard disks one, which will make your computer faster)).
I placed them in another casing, and they were recognized by my mac, but the information wasn't readable (therefore I thought it is in raid, because I thought one kind of raid split your information up, so you will only see halve of your file: no file). But they both still worked. But not in the old lacie casing.
I don't now if your casing is damaged (in which case you should buy a new one) or that your hard disk is dead (because mostly when your hard disk is making funny (not funny) sounds, it's most likely it's gonna dye (haha, I mean die).😛
I'm having to much spare time, so I wrote this lifestory, hopefully it will help you. At least it filled my time.