Mac Pro 2009 4,1 power-on issue

I have a 2009 Mac Pro 4,1. I've been having an issue powering up. I press the power button and then nothing. Then a click. This same thing happens repeatedly. When I cut the power (on my surge protector) and power back on, then the machine boots. Consistently, the Mac will not boot unless I cut the power to it and then power on. I've gathered that this may be a switch of some kind or the power supply? Any suggestions appreciated! Thanks in advance!

Mac Pro (Early 2009), OS X Mavericks (10.9)

Posted on Nov 30, 2015 7:09 AM

17 replies

Corpsickle Author

Level 1

9 points

Dec 11, 2015 8:10 AM in response to Corpsickle

Thanks for the suggestions, all.

Ultimately, I ordered a new power supply and... problem solved.

https://www.macpartsdepot.com/index.php/614-0454-980-watts-power-supply-early-20 09-mid-2010-mid-2012-mac-pro-a1289-614-0454-dps-980bb-2.html

There was obviously a relay of some sort that was resetting when I would cut power.

Good luck!

Dec 11, 2015 8:52 AM in response to Corpsickle

Glad to hear it's finally working and thanks for the feedback. Looks like having Apple replace the PS even though only the battery was diagnosed as the problem was a good move.

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Mac Pro 2009 4,1 power-on issue

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