Chosen Solution
I tried to boot my Mac Pro and it would not do anything when I pressed the button. I changed power cords and got a power light button response but then went out. I then went through the SMC reset. Now the power button when held for 15 seconds responds by the power light flashing for several seconds and a beep tone then the power up sound but nothing happens. No gray screen or otherwise on the monitor. The monitor light goes on when the power button is pressed. All during the process the cooling fans are on high. Any suggestions?
Probably needs a new power supply check the diagnostic lights. Third link, on page 155… says 08 but 09 similar. If this answer is acceptable please remember to return and mark it.
I seem to have a similar problem. I think some water got in my Mac Pro as I left the window open one night and there was a Thunderstorm outside. Next day there was evidence of some drops of water around the pro and nothing worked. I opened up and checked it and there was only evidence of one small drop of water on the bottom circuit card (interconnect board). So I dried it and left the components for a full weekend in a warm room to dry out fully. I re-assembled and started it, the lights came on on the power supply panel, the External hard-drives stared up; but the screen did not start up. I have ordered a new power supply - lets hope this is the problem - otherwise things could get very expensive !
