I had an external dvd drive and it had a usb out and power supply in. I plugged in the power supply and then plugged in the usb to my
Mac Pro (Early 2008) and the power went out and will not come on again. Is there a fuse I can change to get it all running again? Thanks!
Mac Pro (Early 2008), OS X Mavericks (10.9.5), FCS 7.0
You should first try an SMC Reset before assuming the power supply fuse is out.
Remove the AC power cord. Press and hold the start button to discharge the power capacitors. Restore power cord. (If it sparks a little, this is not a blown fuse problem.)
Attempt to power on as usual.
There is a fuse inside the power supply, but the supply and its octopus of wires must be removed from the machine and the metal box must be opened to get access to it. It is VERY unusual to blow this fuse -- i have never seen a report of a blown fuse here.
Another possible issue is the 3 Volt non-recharging coin cell used to maintain the parameter RAM. If it is old and it is below the nominal value, it can fight with the 3 Volt always-on power supply needed to start up.
You should first try an SMC Reset before assuming the power supply fuse is out.
Remove the AC power cord. Press and hold the start button to discharge the power capacitors. Restore power cord. (If it sparks a little, this is not a blown fuse problem.)
Attempt to power on as usual.
There is a fuse inside the power supply, but the supply and its octopus of wires must be removed from the machine and the metal box must be opened to get access to it. It is VERY unusual to blow this fuse -- i have never seen a report of a blown fuse here.
Another possible issue is the 3 Volt non-recharging coin cell used to maintain the parameter RAM. If it is old and it is below the nominal value, it can fight with the 3 Volt always-on power supply needed to start up.
Well, I bit the bullet and took my Mac Pro to a local repair shop. They replaced the faulty power supply and put in a USB 3.0 card and now I'm up and running! It wasn't cheap, but getting it running again is priceless. Apparently, I fried the USB circuits as well as the power supply by plugging in an external DVD drive that I had also powered up. Ne're the twain shall meet!
Holding the power button down with the plug makes sure you get all the stored voltage out to get a good Reset. Otherwise you have to wait an hour or overnight.
That battery can be replaced with a CR2032, used in garage door opener controls and car-key fobs.
Thanks. It could be, but all of my USB 2.0 inputs no longer work, so I must've fried them with the external powered drive. A new USB 3.0 card solved the input issue, however. My bluetooth no longer works, too. I'm lucky to get the tower back and functioning.
I replaced the battery and tried holding the start button with the power plug in and out. Still no startup. Sometimes I hear a click when pressing the start button.
Thanks.
I doubt that the DVD Drive caused it. More than likely it was just a coincidence. I have a 2010 MacPro with a BluRay burner plugged in and it's powered by it's own power supply. I also have a self powered USB hub installed which run 2 USB external drives and at any one time at least 2 other drives in addition to what is already connected. I am in fact in the market for a replacement power supply in my spare time just to have one on hand in case.
Did the power go out as a direct result of plugging in this drive, or was there merely a general power outage later?
Yes, the power on the Mac went out and will not come back on.
That is, the usb drive caused the power to go out.
No luck with holding the power button without the plug in. I will replace the button battery soon.
I replaced the battery and tried holding the start button with the power plug in and out. Still no startup. Sometimes I hear a click when pressing the start button.
Thanks.
blown fuse Mac Pro (Early 2008)
