Path: utzoo!attcan!uunet!wuarchive!brutus.cs.uiuc.edu!apple!motcsd!hpda!hpcuhb!hpcilzb!nino
From: nino@hpcilzb.HP.COM (Nino Mateos)
Newsgroups: comp.sys.mac
Subject: Hard Disc Failures
Message-ID: <870284@hpcilzb.HP.COM>
Date: 23 Aug 89 15:47:03 GMT
Organization: HP Design Tech Center - Santa Clara, CA
Lines: 22

There are clearly two different types of disc boot up failures being 
covered in these notes recently.

The first is the failure of the drive to start spinning at all.
This is fixed by "kickstarting" or putting the Mac or drive on its face,
 or some other abnormal position. This has been explained as 
bieng caused by the heads sticking to the surface of the media
or a dead spot on the rotor of the drive motor. Hey, I can understand this! 

The second failure still has me puzzled. This is the failure of 
the Mac to recognize the drive after it has spun up. Turning the drive 
(power) on and off again will (eventually) bring it back up to where the
Mac will recognize it. The only plausable explanation for this so far has 
been a bad EPROM on some of the older Macs. For those of us with 
more recent Macs, the EPROM explanation is not our answer. 
Somebody out there has got to know what is going on inside these
drives. Those of us out of warranty would appreciate some ideas as to what
the problem is. I, for one, am facing the day when the on-off power 
cycle will no longer bring it up. Does somebody have a software "kickstart"?

Nino Mateos
nino@dtc.hp.com