It was running great until a few weeks ago when it stopped being able to sleep. However I tried to initiate sleep, it would always shutdown instead. I googled around and found a suggestion that it might be the PSU.
A couple of times, during testing I found that after shutting down, I was unable to immediately restart it. Pressing the front panel power button seemed to have no effect. Each time it did actually work after being off for some minutes (maybe half an hour, not rigorously tested).
Today we had a power black out which crashed the Mac. Not normally a problem these days, but now it will not turn on. When I press the power button there's a click from where the PSU is located, but nothing happens. No fans, no chimes, no HDs. Silent and then after maybe 10 secs another click which seems to indicate it gave up whatever it was trying to do.
Following the troubleshooting procedures in the manual reveals that when connecting to power and also when disconnecting, both OVRTMP warning LEDs flash, as they should. Also, when pressing the DIAG LED button the 5V STBY LED lights amber. So trickle power is apparently ok. But, holding down the DIAG LED button does not illuminate any other LEDs, in particular the PSU PWROK remains off.
I have tried removing all peripherals etc but it makes no difference, so I have come to the conclusion that my PSU has been failing for some time and has finally died. Not completely, but enough to prevent startup. So…
Any comments on my diagnosis? Reasons why my conclusion is incorrect?
Can anyone suggest where best to obtain a replacement PSU? eBay is of course a possibility, but another used one may not be an improvement. Are they available new, or reconditioned from anywhere?
I am in the UK, but not beyond the realms of possibility to get one shipped here from elsewhere. The big question is who can supply a known good (new or refurbished) PSU?
A couple of times, during testing I found that after shutting down, I was unable to immediately restart it. Pressing the front panel power button seemed to have no effect. Each time it did actually work after being off for some minutes (maybe half an hour, not rigorously tested).
Today we had a power black out which crashed the Mac. Not normally a problem these days, but now it will not turn on. When I press the power button there's a click from where the PSU is located, but nothing happens. No fans, no chimes, no HDs. Silent and then after maybe 10 secs another click which seems to indicate it gave up whatever it was trying to do.
Following the troubleshooting procedures in the manual reveals that when connecting to power and also when disconnecting, both OVRTMP warning LEDs flash, as they should. Also, when pressing the DIAG LED button the 5V STBY LED lights amber. So trickle power is apparently ok. But, holding down the DIAG LED button does not illuminate any other LEDs, in particular the PSU PWROK remains off.
I have tried removing all peripherals etc but it makes no difference, so I have come to the conclusion that my PSU has been failing for some time and has finally died. Not completely, but enough to prevent startup. So…
Any comments on my diagnosis? Reasons why my conclusion is incorrect?
Can anyone suggest where best to obtain a replacement PSU? eBay is of course a possibility, but another used one may not be an improvement. Are they available new, or reconditioned from anywhere?
I am in the UK, but not beyond the realms of possibility to get one shipped here from elsewhere. The big question is who can supply a known good (new or refurbished) PSU?
