Conference 7.286::macintosh

    I'm just wondering if anyone has any suggestions....
    My assumption right now is that the mother board is toast...

    One of the MacLCs at our school wont boot.  You turn it on
    and it shows a floppy disk icon with a question mark (blinking?)

    At that point I can shove in a system startup floppy (that works
    fine on other Macs in the lab) and it gets spit right out.  I can reboot
    the system (3 finger salute) with that floppy in there and
    after thinking for a little while the floppy gets ejected and the
    blinking icon appears.

    I plugged my EZ135 with a cartridge containing a good system
    folder and rebooted...and as soon as it touched the EZ135 I got a
    SAD MAC with the error codes...
    0000000F
    00000001
    I think this means 'bus error' but have no idea what to do with it.
    (the EZ was at SCSI ID 5).  I assume that the internal drive is at 0.

    I removed the 2 1MB Simms in the SIMM slots...did not change the problem.

    I opened the system and removed the hard drive and rebooted with the
    floppy...same problem.  Eject and blinking ? Icon.  I removed the
    floppy and tried it in a new system and it worked fine.

    I rebooted the system holding down Option/Command/P/R to Zap the
    Pram and let it cycle a few times but it rebooted just the same...
    blinking ? Icon.

    I have not replaced the battery....might that cause this level
    of problem?  I have no idea if its good or bad.

    Not sure what else to try....
    Any recommendations appreciated...
    bob

    The problem is most likely a combination.
    
    First, I'd say that the internal HD is broken - dead or possessed of a
    blown boot block or defective System file.
    
    Second, and this is purely speculation formed from stuff I found on a
    Web search, it looks as if there is a defective write-protect switch in
    the floppy drive, or else you had the disk protected.  There's a
    documented problem with At Ease for Workgroups and certain PowerBooks,
    in which booting the system from a locked volume fails and then causes
    the NEXT boot to issue a Sad Mac with an 0000000F/00000001 error. 
    This is what you saw when you tried to boot from the EZ135, and I'm
    going to guess that the LC is doing the same thing the PowerBooks are
    doing.  If there's a problem like this in one version of the system,
    the same problem may be lurking in others.

    If the internal HD is broken (as suggested in .-1), you might try
    holding down SHIFT-OPTION-COMMAND-DELETE when you power up. This forces
    the Mac to bypass the internal drive and search for another boot
    source, in this case, possibly your EZ135.
    
    This worked for me when I lost the system file on the hard drive in my
    PowerBook.
    
    	/Harry
    

Bob

If you haven't tried the battery, you might want to give it a try.  I've
replaced approximately 10 batteries in LC, LCII, LCIII, and Performa 400
systems over the last year.  I've seen some very weird things happen when
the battery dies like hardware acting as though it's shot.


John

    Battery test for sure. One day it works and the next the machine is
    dead. Happened to me.
    
    I recently went through the bad hard disk problem, killed my internal
    drive, then swapped in a 130MB fo rthat and when I went to back up my
    fresh MacOS install, killed that drive too. In both cases, this happed
    after I had added about an 8 foot SCSI cable to the machine.
    
    Aha, says I, data problems on the SCSI bus, now I had two hard drives
    with corrupted something or other, but very serious as I kept getting
    the sad mad with the hex numbers or the flashing floppy icon with the
    question mark.
    
    I recovered both drives, the non-Mac drive by booting the system with
    the power off the drive, then plugging in the power on the drive and
    then formatting it completely and the Mac drive by doing the same thing
    basically, except I unplugged the SCSI cable and plugged it back in
    when the system was booted.
    
    I did not try the four key procedure as previously mentioned two notes
    back, sure wish I'd know that, it might have worked and saved me the
    dangerous potential for some serious damage.
    
    I now am looking into purchasing some really short scsi cables for
    everything.
    
    rtt

    Re .167
    
    Unsolicited testimonial:  Buy APS cables.  Their quality is, in my
    experienced, unmatched.  They also have a tiny 1-foot-long cable
    designed especially for stacks of drives, to shorten the bus and get
    rid of the rat's nest of cables.

rrt

I have run with SCSI chains around 20' long. Did you disable termination on 
one of drives. What is you exact configuration? If your SCSI chain is just
the system an internal drive and an external drive, you don't have length
problem. The problem is termination or a bad cable. (IMHO)

mark