[rescue] v250 power supplies?

[Ray Arachelian]

I've tried playing with it some more...

I pulled out all the PCI cards, and even the LOM, unplugged power to
everything except the motherboard and attempted it to turn it on, but it
behaved the same.
PS's show a green light for a brief moment, then they spin up the fans
on the case + CPU for a second and power off.

I unplugged power to the mother board and this time both power supplies
stayed green for a long time.

So I guess it might be the motherboard.


Ray Arachelian wrote:
> Hi,
>
> I just got a V250 that was destined for scrapping, but I can't power it
> on.  When I plug in power (110V) to both PS's, they briefly blink the
> green LED, then both switch the maintenance amber LED.  The front
> maintenance amber LED turns on as well.
>
> The PS's are getting power as I can feel their fans running.  If I hold
> the front power switch for a few seconds, I see the case fans and the
> CPU fans spin for about 1-2 seconds and then they stop.  I also see the
> DVD drive briefly get power, but that's it.
>
> I've tried unplugging power from the DVD, swapping the power supplies
> around, powering just from one or the other, etc.  no luck. :-)
>
> I am however able to login and talk to the LOM, which says both power
> supplies need maintenance.  The LOM has "On" for undervoltage under
> showenvironments(I think).
> Is the undervoltage flag for the output of the power supplies or the
> input (120VAC vs 240VAC?)  I've seen similar behavior for v490's if
> hooked up to 110V instead of 240V - the LOM works but the system won't
> power.   From docs.sun.com, and the label on the power supplies, this
> box can work with 110-240V, but the behavior is a bit strange.
>
>
> So I'm wondering is there a common failure with these power supplies?  I
> find it odd that both have failed, but yet, either one alone can provide
> power to the LOM.
>
> Should I just buy a replacement power supply (some of which I see are
> quite expensive). 
>
> Could it be something else that's wrong?
>
> I certainly wouldn't mind taking a power supply apart and replacing
> parts, but which parts should I look at?
> (Alternatively, is there any other way to power this specific
> motherboard via any alternate power supplies from other machines?  Since
> this is for home use, I don't really need dual power supplies or to fill
> all 8 disk slots.  Anyone have pinouts for the power plugs on the
> motherboard?)
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