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Eldad5005

macrumors newbie
Original poster
Apr 18, 2020
2
1
Hi
I’m trying to find a manual on the diagnostics light inside the Mac Pro late 2013 a1481 (cylinder)

currenlty I have only 4 less lighting up (out of 7) and Mac won’t start up
No chime sound,usb backlit keyboard not getting Light.
I’ve tested the voltage and it seems to get more then 10v on pins on the main power supply, replace power supply but still same problem.

I’ve tried changing the cmos battery with no vail

The only thing left is checking with another main board or video cArd but I doubt that’s we’re the problem is

I would appreciate if anyone has a link to the diagnostics leds on the board- I’ve looked all over but couldn’t find any documentation on this.

tnx
 
I found the service manual on eBay. It does indeed have a section on the diagnostic LEDs.

[automerge]1587886178[/automerge]
The block diagram only shows half the image in the manual, but here's the full image. It looks like the PDF was created from another source. Probably a web based Apple confidential resource.

 
I bit and paid the $1.99 for that eBay service manual. It is a PDF capture of the web manual using "PD4ML. HTML to PDF Converter for Java", not the true Apple manual PDF. That's why the diagram is cut off as it is formatted for page.
[automerge]1588006518[/automerge]
 

Attachments

  • mp-2013-late.pdf
    14.6 MB · Views: 3,180
Is it safe to assume Apple stopped issuing PDF format manuals after the Mac Pro 5,1 and now keeps all of that web based? It seems to be an industry-wide trend. Also, from reading a good part of the manual there's no way I would attempt doing a CPU change on one of these myself without having the proper tools. It makes the iFixit guides look like the product of rednecks. And also helps me understand Apple's position on only allowing certified technicians to do repair work. Due to the complexities and sensitive nature of the equipment I can understand how they would want to avoid the liability of end-users working on them.

Thanks for sharing that BTW. I wasn't going to share it because I didn't want to hurt someone's little revenue stream, but of course it isn't something they can legally sell.
 
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my 2013 Mac Poo failed to startup yesterday 🤬 i have already spent £700 a few years ago getting it repaired, since then all it did was sit around as i still use the old 5.1s in the office.

pressing the diagnostic button i get 5 green LEDS

using a multimeter i tested the bus bars and it reports 12v, i have ordered a new PSU just to test.
 
my 2013 Mac Poo failed to startup yesterday 🤬 i have already spent £700 a few years ago getting it repaired, since then all it did was sit around as i still use the old 5.1s in the office.

pressing the diagnostic button i get 5 green LEDS

using a multimeter i tested the bus bars and it reports 12v, i have ordered a new PSU just to test.
Hi krakman, did you solve the problem with a new power source?
My mac pro does not start, leds seem to be ok on the power source board pushing led buttons 2,,3,5,and 8 are green and no one is lit on cpu board. It is frustating not to know whats happennig
 
I am also having similar issues - Although the back I/O lights up - I'm missing #4,6,7 diagnostics lights - I thought it was the GPU so swapped them with another MacPro I have - but they're fine, have swapped everything but the logic board and CPU. I have a feeling its something on the main CPU riser card.
 
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Hi krakman, did you solve the problem with a new power source?
My mac pro does not start, leds seem to be ok on the power source board pushing led buttons 2,,3,5,and 8 are green and no one is lit on cpu board. It is frustating not to know whats happennig
Did you ever find a solve? Seem's we have the same problem
 
I got the same problem. Then i replace the coin battery and restart the Mac but still the same problem. I spend a lot of time on it and i was able to start many times without the cover. First boot of the mac was done when i was pressing the diagnostic button. Then i was able to boot many time with the cover out. Then i tried in normal configuration and the mac cannot reboot. Apple they don't care about the old model.
I got a problem with a macbook pro mid 2010 and compagny in Paris solve the problem but it cost 350 euros and the Macbook pro is still alive. Maybe i will try to talk with them to see if they can do something about it and let you know.
 
I bit and paid the $1.99 for that eBay service manual. It is a PDF capture of the web manual using "PD4ML. HTML to PDF Converter for Java", not the true Apple manual PDF. That's why the diagram is cut off as it is formatted for page.
[automerge]1588006518[/automerge]
Thank you so so much for this ❤️
 
Yesterday my Mac dead with the yellow light on the CPU riser card. All the light on the I/O board are green. It's really frustrated when not to known what is actually happening.
 
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