How to test the PSU with a multimeter

I have a late 2013 Mac Pro, it is totally dead, no illumination at all when power button is pressed. totally dead.

I want to rest the PSU with a multimeter, but I am not sure what terminals to attach my multimeter to and what readings I should expect

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This image shows the terminals I am just not sure what I should be expecting (Thanks for the person who originally posted this)

I am aware of the diagnostic LEDs. however all I get when I press the test button is the 11V LED, and that LED only stays lit when the test button is depressed.

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Based on this post https://logi.wiki/index.php/Mac_Pro_6,1_... I was under the impression the 2nd LED down/11V LED should remain lit whenever the power lead is attached however this is not the case with me. If this is incorrect, could someone explain to me how the diagnostic lights are supposed to work please? FYI the flex error LED lights up red when the flex cable is disconnected so that appears to be working.

Any assistance would be greatly appreciated. I don’t want to splash out on a new PSU if thats not going to get me back online. TIA

crwdns2934089:0crwdne2934089:0 crwdns2934093:0crwdne2934093:0

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Did you use a magnet to enable the system?

crwdns2934271:0crwdnd2934271:0crwdne2934271:0

Thanks for replying, I didn't until just now when I read this, but it did not seem to make any difference to the diagnostic lights. its a pretty strong magnet and it holds itself to the side so its defo on there. But I still just get the 11V light

when I apply a multimeter to the terminals on the top, with the multimeter set to 20v I get a reading of around 0.78.

Do you think thats the PSU?

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