The symptoms indicate there is a problem with the drive, how it is connected, or with the computer used for troubleshooting. The next best step is to change physical variables, and find a simpler problem than a broken product.
- Change the data cable. A failure in the cable can cause this issue.
- Change the external power supply or cable. If a different LaCie product is available, borrow the power cabling from that unit to see if the problem is in that component.
- Change the computer you are using. Computer problems can manifest themselves in different ways. Even if the computer appears to be working properly, this is a worthwhile test.