Dead WD 1.5GB elements?

A few days ago my… cat… tripped over the cord of my 1.5TB WD elements drive and it hasn’t been working correctly since. Today when I plugged it in, I was able to see all the folders when the drive mounted; but I wasn’t able to copy anything. When I returned later today, the drive wouldn’t mount or anything. The light on the back of the unit is flashing a white light. 

Based on this, is it possible to tell whether it’s the chipset or the hard drive? What do the light sequences mean? 

EDIT: I’d also like to note that when I plugged the device into a mac, nothing was listed under USB in the system profiler… all my other drives; regardless of whether a HD is attached, will still show the chipset listed there.

I do not know much about Mac. Your drive may have sustained physical damage if it toppled even on the desk. Also check visually if the USB ports on the drive and the port connected on PC side for possible damages.  Try changing your cable. Please note that all USB cables visually identical are not capable of connecting USB drives. If in doubt, try using good quality brand new cable.

If you can SEE your drive listed on device manager, you can proceed with following instructions. If not your drive has a hardware/connection fault and contact WD support for their support if possible.

 Try using HDD Regenerator 2011 to scan your disk if it is show on device manager. Search on My Passport forum for my messages related to HDD Regenerator 2011. It will restore most of the damaged sectors without destroying your data and make your drive usable.

Prior to that, you can use HD Tune or WD DLG diagnostic utility to test your drive (if it is visible on device manager). Please do not use Windows Scandisk to scan your drive.

Good Luck!