MP 1,1-5,1 macpro 3,1 have to unplug to boot

[Tex Tiles]

Hi all, I have had a problem with my macpro 3,1 for a long time where I have to keep it unplugged when turned off or else it won't boot. It just clicks and doesn't chime or fan or anything. So then I have to unplug it, wait 10-15 minutes and then plug it back in and it will boot normally and run for as long as you want (days on end) but when you shut it down, again you have to unplug it for 10-15 minutes. So I don't think it's actually the power supply as it runs perfect once booted, but perhaps someone else has had this problem and found a solution.

I suspect it's got something to do with the mechanism that tells the power supply to boot etc. I heard that this was a somewhat common problem, so any wise words of wisdom would be appreciated. Thanks

 

[Macschrauber]

have you checked the rtc battery?

 

[Bigwaff]

Changing a Battery in mac pro 3.1 - Mac Pro First Generation

How do you change the battery in a mac pro 3.1 - Mac Pro First Generation

www.ifixit.com

 

[Tex Tiles]

Changing a Battery in mac pro 3.1 - Mac Pro First Generation

How do you change the battery in a mac pro 3.1 - Mac Pro First Generation

www.ifixit.com

yes, thanks. it's not the battery unfortunately.

 

[Macschrauber]

you can measure it, below 3.0 volts you should replace it with the same BR type.

Minus on chassis, plus on the top side of the battery, not even needed to pull it out.

 

[tsialex]

To have to unplug the power cable and wait until the PSU discharge itself is a classic sign of a defective PSU.

If you are comfortable opening a PSU - high voltage and etc - check if any of the caps are leaking/bulging also if any other component are toasted/burned.

 

[Tex Tiles]

To have to unplug the power cable and wait until the PSU discharge itself is a classic sign of a defective PSU.

If you are comfortable opening a PSU - high voltage and etc - check if any of the caps are leaking/bulging also if any other component are toasted/burned.

Is it. Thank you for that, I had thought it was some control mechanism, because if it is on and I press restart it starts fine, but if I force power down or even just off but plugged in it won’t power up.

I didn’t want to replace the power supply to only find after it was something else.

 

[Tex Tiles]

It’s been doing this for about 8 years with no change. I do the workaround of just unplugging it when not in use, but I am in the middle of having to rearrange my hard drives and it is really testing my patience to have to wait 15 minutes everytime I shut down to swap a hd.

 

[Tex Tiles]

you can measure it, below 3.0 volts you should replace it with the same BR type.

Minus on chassis, plus on the top side of the battery, not even needed to pull it out.

Yes thanks, I replaced the battery previously. Didn't help.