I've looked at reference guides but haven't found an exact diagram for this model. If anyone has experience with this board, I'd appreciate details on:

• The exact location of the Power Pads
• The best way to short them to turn the system on
• Any precautions I should take to avoid damage

If you have images, schematics, or detailed descriptions, they would be extremely helpful. Thanks!

⟐ Commented May 23, 2025 at 10:30 MST

⟐ Commented March 02, 2025 at 13:49 MST

I just got one yesterday and the fans don’t power on

⟐ Commented July 26, 2024 at 16:40 MST

⟐ Edited February 24, 2024 at 7:34 MST

thanks in advance

Lethal

The power button apparently has no function anymore. I can since then only can start my Mac Mini from late 2014 by plugging out the CR2032 PRAM battery and plugging it back in.

Curiously, the starting of the boot process including the chime sound occurs after plugging the power cable and not pressing the Power On button.

Another thing is, that I only can restart the system, when the SSD internal drive has not been connected to the logic board. So, if I plug out and in the Same battery or even plug in a new PRAM battery and at the same time I connect the internal Hard drive to the board, I am able to start only once. When I do not Connect the Hard drive, I can start the system inifinite times but without pressing the Power On button.

The Power On Button seems to have no damage and it is still connected to the board with two wires.

Can anyone help me? There is an 8pin BIOS related device right in front of the L-wise formed black unit.

Has it anything to do with that. In another topic, someone heated up the logic board to 180 centigrade degrees 15 minutes long and could get rid of an issue.

Do you think, this May help me?

Thanks

any help would be greatly appreciated

thanks

Lethal

Chime

Light

Fan

No signal output

Everything was fine, swapped SSD and now this - what has happened?

I didn't know where to post it, but I thought I'd post it here. We tried to tidy up a friend's Mac Mini 2011.

However, it was given to the service before and the service stated that it would no longer be repaired and that the motherboard had to be changed.

When I took the device and opened it the R56D coded SMD inductor on the motherboard is missing.

If the service dismantled it, why did they remove it? Is a separate mystery...

My question is, where can I find this part? Even if I find a spare motherboard, I find it unnecessary to spend just for this part.

Thank you very much to everyone in advance.

⟐ Edited September 29, 2022 at 5:20 MST

Tried to modify the BIOS\EFI chip using a CH341A, but it didn’t go well. Killed the chip, and now I’m using a W25Q64FW instead of the original MX25L6406E.
The question is: is W25Q64FW gonna work (it’s also a 64mb 1.8v chip) and where can i get an EFI dump for 820-3227-B board with and i5-3210M?

Don’t mind doing the board work if needed.

Thanks!

⟐ Commented December 21, 2021 at 10:55 MST

I tried searching online and couldn’t find anything related to this, the closest thing I could find was the CPU fan jumping to 100% after the machine started to boot. I’m worried I might have killed it somehow (couldn’t have been static since I had an anti-static wrist strap on and confirmed I was grounded)

⟐ Commented December 20, 2021 at 17:48 MST

I attached the picture with the capacitor location highlighted in green…

⟐ Edited by author March 18, 2021 at 9:59 MST

⟐ Commented March 13, 2021 at 15:06 MST

Please help!  Mac Mini 2012 Late, A1347 (820-3227) looking for the answer .. Turns on, startup sound is on, fan is on, USB powered (even router LAN network can be seen in Apple ) Problem with no picture, no hdmi output, no DVI output none  .. I disassembled it but based on the motherboard measurements everything “looks good”.  I suspect the PS8401A ic error .. Got new flash and memory ic, situation is unchanged, unfortunately nowhere can I find circuit drawing, not even in paid places.

 I looked through the sheet, I didn't find a burn short circuit.  

(Test trial of two working hdmi and one DVI cable and trial of three monitors and one tv)

Thanks in advance!

Joeteso

⟐ Reopened January 11, 2021 at 8:01 MST

When you restart it, about 7 times out of 10 it will shut down just a few seconds after the startup chime. It doesn’t show the “NO” symbol, or anything else - the startup chime sounds, the grey boot screen appears, and then it shuts down like someone’s pulled the power cable out.

If you keep trying, eventually it will boot normally and then everything will be fine - it will run happily for days, until I need to boot into a different OS and then the problem reoccurs.

It’s definitely NOT the hard drive (actually an SSD) - I’ve replaced it with a brand-new one with a fresh OS install, and the same thing is happening.

It’s also not the PRAM or SMC - I’ve reset both (and replaced the PRAM battery), with no effect.

Could it possibly be the fan? After 12 years of being on almost 24/7 (generally with just a few weeks off each year), I’m wondering if the fan bearing is starting to go bad, so isn’t always spinning up as well as it should and the machine is able to detect this and immediately shut down?

⟐ Commented January 05, 2021 at 8:47 MST

I’ve bought a mac mini A1283 from ebay (it was a job lot) and.. as it doesn’t work as it should, I’ve decided to investigate.

There was a problem with the power button… I suppose that the guy hadn’t googled how to disassembly it… he has ripped down the power connector on the motherboard.

Now it’s ok, but… if there is the interconnect board with (or without) HD and with (or without optical drive), the 2nd green light (led602) on MB will blink for a moment, but the mac mini will not turn on. If the interconnect board is not plugged, I have the 2 green lights and the mac mini power up… but without OS is a little bit useless :)

I have to say that the guy has also broke up a little bit the black plastic of the interconnect board plug (on the MB), but the pins are still there, it’s only a little bit of plastic (which I could glue back).

More infos : I’ve change the pram battery = same problem

I’ve changed the RAM = same problem

Any ideas ? Sorry if it’s not so clear what I said :)

Thanks a lot and have a nice day,

Kat

⟐ Edited by author December 18, 2020 at 5:02 MST

Did a TechTool Pro “Fan Test” and it failed. The fan never engaged durning the test. I will open Mini back up and check connectors. Hey, it has never come on during use anyway, so I’m not going to sweat it if it won’t come on anymore. Better than always on full blast!

Well, wishful thinking all round!

Found that replacing the Hard Drive sensor cables did not solve the fan running all the time issue. Thought it had, but turns out the reason the fan didn’t come back on full blast was that the ribbon cable connector was at an angle and not fully seated. Once I plugged it in all the way, the fan came on at boot and stayed on full blast again.

Unless someone has a better suggestion, I’m going to leave the fan cable unplugged. As far as I could tell, before replacing the SSD, the only time the fan spun up was when doing a fan test. Maybe it did come on at times at low speed I couldn’t hear, don’t know.

It is all back together according to the IFIXIT instructions. SSD nice and fast, but fanless now. Hope it will be fine without fan.

⟐ Edited by author November 25, 2020 at 12:00 MST