2011 Mac Mini 820-2993-A no power

[Maciej.Klm]

Hello all,

This is my 1st post on this website, but I'll try to be as clear as possible. I've bought 2011 A1347 (820-2993-A) mac mini for spare or repair on ebay with intention of fixing it. After short troubleshooting I'm sure that PSU is OK as I'm getting stable 12V from it. I've started checking other components and found that power rail marked 39 C13 is getting stable 12V from PSU side, but I'm only getting 0.1V on the other side. I don't have access to any schematics, but 0.1V sounds way too low. Can anyone tell me what the part number of that component is, or maybe something similar that I can replace it with. I'm adding a picture of the suspect

Thank you in advance.


Maciej

[Maciej.Klm]

Re: 2011 Mac Mini 820-2993-A no power

Guys,

Any help would be appreciated

[caspian]

Re: 2011 Mac Mini 820-2993-A no power

0.1V is considered to be no voltage in laptops. you have to find schematics or boardview of this mainboard to continue repairing. have you search this forum?

[Maciej.Klm]

Re: 2011 Mac Mini 820-2993-A no power

Hi Caspian,

Yes I've searched this forum as well as internet. There are some sites that this can be downloaded form, but obviously all of them are charging lots of $$$. Also tried to search on torrents, but so far no luck at all. Once I manage to find anything I'll post a link here, just in case other people mighty need it as well.

Regards,

[caspian]

Re: 2011 Mac Mini 820-2993-A no power

you do not need to pay for the schematics. Probably, someone will upload it here.

[Maciej.Klm]

Re: 2011 Mac Mini 820-2993-A no power

Well fingers crossed

[piernov]

Re: 2011 Mac Mini 820-2993-A no power

No schematics for 820-2993 AFAIK. Therefore someone asking for money is probably a scammer.
I don't see what's wrong with having 12V on one side an 0V on the other side of a capacitor.

[Maciej.Klm]

Re: 2011 Mac Mini 820-2993-A no power

Thanks Piernov, do you know how to identify specs that component or others?

[ablacon64]

Re: 2011 Mac Mini 820-2993-A no power

Sorry for being late. That is a capacitor and the voltage is OK, that "0.1V" side is ground. You have another problem.

[Rayskate]

Re: 2011 Mac Mini 820-2993-A no power

I have Mac mini same model that has limited power on the board as well. Does anyone have any kind of diagram or know of anything to help check power rails to fix it?

[Stephen]

Re: 2011 Mac Mini 820-2993-A no power

Hey man, so common issue in this is a bad BIOS chip. What you are most likely experiencing is a either a Bad Bios chip. I Had a no power issue and replaced the bios chip on this and it turned on. Not saying it is but do a Bios Chip test and see if the BIOS has failed. I repaired a 2011 recently. I was just curious if the Bios failed and it was something that truly was the issue. Its an easy repair. If you have a Programmer easy work, if not you can buy one on eBay for it.

[Stephen]

Re: 2011 Mac Mini 820-2993-A no power

Let me add to my statement, I ALSO am not saying it is a Bios Chip as well. But I have got a few of these recently with Bad Bios Chips. I had a few Mac Mini 2011 laying around for donor boards and took their bios off and replaced it and they turned on. I would just start there IF THERE was no signs of water damage.

[ACS-Repair]

Re: 2011 Mac Mini 820-2993-A no power

I just repaired a 2011 Mac Mini that would not power up. The LED on the front and the fan would come on for about 1 second, then power off. Is this the problem you are having? If you hold the power button on and plug the Mini in (safe mode) all of your supplies may come up so you can measure them at the coils.

[david zhao]

Re: 2011 Mac Mini 820-2993-A no power

I just repaired a 2011 Mac Mini that would not power up. The LED on the front and the fan would come on for about 1 second, then power off. Is this the problem you are having? If you hold the power button on and plug the Mini in (safe mode) all of your supplies may come up so you can measure them at the coils.

Hi ,


I have the same issue. I can hold the power on button, then plug in the power cord, system turns on with high fan spinning. What is the actual issue causing this symptoms? Normal press power button, the power does not come on, but I can hear the hard disk spinning, no green led on the box though.