At 06:08 PM 9/8/99 -0500, you wrote:
Thanks Tony and Joe!
Just before dinner I powered up the drive again. After the 30second spinup,
the heads move out to cylinder 0 and the drive ready light comes on.
I tried very gently moving the head assembly both forward and back. The
thing wouldn't even think about moving. I applied more pressure (a pretty
fair amount IMHO), and the head assembly still won't budge at all.
That sounds right. I'm sure your power supply and voice coil are good.
I hit the
unload switch and the drive starts to brake, but the
heads don't retract.
Very strange. The only thing I can figure is that it uses the battery to
retract the heads even for normal operation and that the battery is shot or
there's an open circuit somewhere. You might try hooking a meter to the
battery and watching it while doing the same operation and see if the
battery is OK. But it's usually easy to tell when one is bad. You might
also look for a relay that opens or closes to supply retract power when you
press the unload switch and try to trace the source of the retract power
back from there. You may find that it's something as simple as a bad relay
contact.
I
immediately move the heads back manually and all is
well (at least no
further HDI).
After dinner I'll start double checking the power supply voltages. Thanks
for any and all input!
Good Luck.
Joe