techknight, If i did my research correctly, I should have seen +5V across pins 24 and 25 of the external DB25 connector if the SCSI bus were working correctly. Unfortunately, I measure no voltage differential between 24 and 25. So, if that's the problem, what's the cause? Is this a hard drive failure or something else and how do I diagnose the problem? The hard drive is configured for SCSI ID 0 with all terminating resistors installed. I appreciate any insight you can provide.