[rescue] SUN IPC PSU - still not working after recap

[Alan Perry]

Not sure where to go with the Classic or the PSU?

The Classic will work with a mini-ATX PSU. But, while it is on my to-do 
list, I haven't finished the work to stuff that PSU and latching relay 
(for the momentary-on power switch) into the Classic/LX PSU chassis.

alan

On 6/6/25 7:00 AM, Ian Litchfield via rescue wrote:
> I have the same issue on my SPARCClassic. I replaced the capacitors in 
> the power supply and now the unit doesn’t power on. It’s pretty 
> frustrating. It was working before I replaced them, but I wanted to be 
> forward since they are known to fail.
>
> It’s been sitting in a box all this time since it stopped working, 
> such a shame. Not really sure where to go with it.
>
> -Ian L.
>
> On Fri, Jun 6, 2025 at 09:14 Andrew Back via rescue 
> <rescue at sunhelp.org> wrote:
>
>     On 06/06/2025 13:42, Jan Liška via rescue wrote:
>     > Hello,
>     >
>     > I’ve started recapping my IPCs using locally sourced low-ESR
>     capacitors.
>     > However, both PSUs I’ve recapped so far exhibit the same issue:
>     >
>     > They power on for a very brief moment (about 0.1 seconds), the
>     5V rail
>     > voltage rises to 2–3V, and then the unit shuts down. I checked
>     the units
>     > for cold solder joints and significant corrosion damage on
>     trails but
>     > found none.
>
>     This doesn't help, but just to add that I've experienced the very
>     same
>     problem and come across others who have also. Hence would be
>     interested
>     to hear if anyone gets to the bottom of what appears to be a common
>     failure mode. Sadly my SMPS fault finding skills are pretty minimal.
>
>     Andrew
>
>
>
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>
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