Re: IIgs repair help

[rwmlodoc@ingr.com (Rich Mlodoch)]

In article <1993Nov12.143419.10176@alw.nih.gov> Jim Owens <jow@helix.nih.gov> writes:
>Right now there is a IIgs with a problem.  It is due to go into a
>Kindergarten classroom in January.  This poor machine will not recognize
>any floppy drive.  Instead, when it is turned on it immediately clicks
>while the light on the box flashes on and off rapidly and the light on
>the floppy drive flashes at maybe half the rate of that on the cpu box. 
>Mrs. Corrado has used the drives (3&1/2" and 5&1/4" daisy chained)
>successfully with other IIgs, and drives that work on other IIgs do not
>work with the injured one.
 
This may be caused by either a bad power supply, bad motherboard, or a
bad card in one of the expansion slots. The GS has a power supply that
can detect an over current or over voltage condition and shut itself down.
After shutting down it comes back up, detects the same condition, and shuts
down again. This cycle continues until you shut it off. That's why you see
the blinking light, the computer is in this cycle. I would first remove all
boards in the box and try to power up. If it goes away, it one of the boards
and you can find it by putting them back in one at a time until it comes back.
If it doesn't go away swap in a power supply from one of the good gs boxes
(it's easy to do). If it goes away the power supply is bad, if it doesn't
the mother board is bad. A mother board swap can be had from Sun Remarketing
for $99 (Sun is in Utah and their in the 800 directory).

>
>A coworker's nephew had a similar thing happen to him and he claims to
>have fixed it by accessing using the Control Panel to reset something in
>the PRAM.  I was instructed to start the IIgs with the Option key down to
>get the Control Panel.  It didn't work, so now I am taking the manuals
>home to see if I can decipher what the nephew meant.  It occurred to me
>that if it is a parameter RAM problem, perhaps the battery is dead, but I
>don't know what happens if that is the case.  Any suggestions will be
>gratefully accepted.
>
If you have the lights blinking you won't be able to get to the control
panel. The lights blinking symptom can be caused by a shorted out
battery. A dead battery doesn't keep the gs down, it causes it to reset
the control panel to the default settings each time you power up. The clock
also gets reset each power up on a dead battery.