Seagate's product manuals aren't always accurate. Try the tape, but also measure the diodes and resistors.
TVS Diode FAQ:
http://www.hddoracle.com/viewtopic.php?f=100&t=86BTW, Seagate's enclosures are configured with a sector size of 4KB, so don't be surprised if you can't see your files in Windows. Instead try a data recovery tool such as DMDE.
Just FYI, there is an 8-pin IC and a 6-pin IC near the SATA power connector. I suspect that these are the load switches for the 12V and 5V supplies, respectively. That is, when the Power Disable pin is active, these two load switches would be switched off.