Hello, i do not know if my smc chip is broken or not, what i know is that in the fan connector i have 12v in pin 1, tacho is measuring correctly in pin 2, pin 3 is always 3.3v and pin 4 is gnd. The problem is that the pwm that controls the speed of the fan is not existent, pin3 is always at 100% so 3.3V all the time. I do not know what chip generates the correct pwn to control the speed. I tried to follow the track that goes to the pwm but i got lost.

Does anybody have the electric circuit of the pwm? or tell me what chip is the smc? i cannot identify it in the motherboard.

I run the diagnostic and i got ( 4MOT /1/140000003: exhaust-6262) the number after Exhaust is the revolutions of the fan so that means nothing, it is maximum speed. There is no speed control because there is no pwn, just a 3.3v signal.

If could see the electric scheme maybe i can identify if it is the smc chip that is broken or maybe some capacitor or resistance.

Macfan software shows the speed of the fan and all the temperatures, everything is ok but the fan speed that has no control regulation.

thank you

⟐ Commented maio 26, 2022 at 13:17 GMT-7

⟐ Answer deleted maio 18, 2022 at 2:17 GMT-7

My Mac Mini Mid 2011 doesn’t power on but I hear clicking (or ticking noise). I replaced the power supply, it didn’t help.

Are there any ideas how to fix it?

⟐ Answered março 31, 2022 at 8:42 GMT-7

⟐ Answer edited fevereiro 24, 2022 at 21:47 GMT-7

I ended up being successful, however in attempting to loosen the logic board screw to allow room to to seat the hard drive as the instructions indicated, the screw was so tight I stripped the screw. After quite a lot of struggle I seemed to get the drive seated and it is functioning.

Is there a way to loosen the screw for any future issues?

⟐ Commented janeiro 25, 2022 at 6:19 GMT-7

Unfortunately, I lost the part. I believe it was that same capacitor (there's a whole bunch on the board), Mine is the Mac Mini 2011 2.5GHz, and when I compare the board here: Mac mini A1347 (Mid 2011) 2.5 GHz Logic Board it's almost exactly the same (coin battery is in the same place). The capacitor is there.

I don’t have the best camera in the world but I hope that’s good enough. Let me know if you need a zoom on a certain section. I should add that I was running the mac headless (through VNC, which does work) after the board stopped displaying out, but I want to repurpose it again

⟐ Commented novembro 09, 2021 at 20:32 GMT-7

Images show left and right sides for comparison.

A thin piece snapped off, it was where the draw box indicates. I was hoping it would not matter…but the old RAM doesn’t work now either. The piece was at the very bottom of the carriers, against the circuit board.

⟐ Answer edited novembro 13, 2021 at 16:23 GMT-7

⟐ Commented novembro 08, 2021 at 10:55 GMT-7

I read that is possible to install 16GB ram (2x8) 1333 MHz and it works well, but is it possible to install 16GB kit (8GBx2), 204-pin SODIMM, DDR3 PC3-12800? Thanks

⟐ Answered outubro 24, 2021 at 0:45 GMT-7

I have tried to reset PRAM and SMC but i cannot tell if they have actually reset, not sure if the sandy bridge based macs use something different.

I also ran the "d" diag utility and everything passes. The machine runs fine the fan is just stuck at 100% and its very annoying.

⟐ Commented agosto 28, 2021 at 0:22 GMT-7

Here’s a list of the issues:

• The Mac Mini will usually not boot up all the way. The progress bar gets to about 60-70% and reboots. After about 3 times of this, the fans get loud and there is no display output (I can fix this by resetting the SMC).
• If the Mac Mini does boot (rare), it will reboot after about 10-15 minutes. I can usually get it to boot after resetting the OS or running hardware diagnostics.

Here’s what I’ve tried:

• Different surge protector
• Replaced the PRAM battery
• Replaced the drive (replaced it with an SSD)
• Reinstalled the entire OS (multiple times)
• Disabled the Dedicated GPU by following this article: https://discussions.apple.com/thread/750....

After doing some research, I’ve seen people that have had similar issues, but fixed them with one of the following:

• Applying new thermal paste. I feel like this probably isn’t the issue because I would think that the CPU/GPU wouldn’t overheat right when the computer boots up, but I could be wrong. Even if this isn’t the issue, I should probably reapply the thermal paste at some point.
• Resoldering / reflowing the graphics chip. I have discovered Radeongate, but not all of the symptoms match mine. For example, a lot of people have said that they see a green apple logo, have a distorted output, etc. but I am not experiencing any of that. As I said above, I have tried disabling the dedicated GPU, but that didn’t seem to help. I do not have much experience soldering, but it’d be worth a try if this is the issue.
• Replacing the power supply

One last note, safe mode works fine. This makes me think it may be an issue with the dedicated GPU. If so, is there a better way (than what I tried before) for me to disable the dedicated GPU to ensure that this is the issue?

Thanks for the help!

⟐ Answer accepted junho 03, 2021 at 8:48 GMT-7

This is my very first post on the forum.

I always wanted to have an Apple computer and I like fixing stuff, so I went on Ebay and bought a 2011 Apple Mac Mini that chimes, but won’t post.

Being a Windows guy I struggled to troubleshoot what was wrong but still decided to give it a go.

I reset the SMC and PRAM, as advised with no success.

After this, I opened it up and removed the hard drive, to see if at least would show on the screen the famous folder with the question mark. Nothing showed up.

I changed the RAM, and while changing it, I powered on the Mac mini with no RAM and it gave me that mono beep complaining of no RAM was detected. That’s why I still believe there’s some live in this thing because it can detected if there’s RAM, it chimes and it powers on my keyboard and mouse.

I replaced the PRAM battery (but used one) but still no video output.

At this point I ran out of ideas…

Also, I noticed that as soon as I power it on, the motherboard gets weirdly hot. Not crazy hot, but too hot for something that it’s not under load.

Is there anything else I could try that I am missing?

Thank you very much in advance or your help.

Regards,

John

⟐ Answer accepted março 25, 2021 at 9:25 GMT-7

I managed to disabled the discrete GPU (Radeon 6630M) and now it boots to desktop but the graphics are pretty awful using the integrated GPU.

My options seem to be:

1. Try to 'reflow' the chip. However, it seems this would only be a temporary fix. Or can anyone recommend a high quality repair service that could fix it in a more permanent way? (reball the chip?)

2. Replace logic board. Second hand logic board $150 to $200 on ebay. Some risk that it would fail again.

3. Buy a new system (most expensive, $800ish for comparable specs).

Anyone else faced this? Any other options to consider?

If you reflow/reballed, how long did it last?

⟐ Answered março 16, 2021 at 14:02 GMT-7

⟐ Answer accepted fevereiro 17, 2021 at 15:51 GMT-7

I have checked that the power supply gives 11.8V on all 4 pairs as of this guide so it appears to not be the problem. Complete Dead - How To Check Power Supply Vs Logic Board

So now I am rightly of wrongly looking at the logic board. I have read in a few other forums of failing capacitors near the power supply on Macs. Can someone point out where in the photos these might be? Other ideas of where/what to check and how are also appreciated.

⟐ Commented janeiro 26, 2021 at 8:10 GMT-7

So I bought this kit.

https://www.amazon.com/gp/product/B00SNM...

The issue is the following. When I put a 8GB module on the bottom slot. I get the 3 beeps 5 seconds pause error. When I put it on the top module it works.

So now I have the original 2 GB stick on the bottom slot and a 8GB module on the top slot. The computer is working and it says it has 10GB of Ram.

Nonetheless I don’t understand why the bottom slot doesn’t work with the 8GB module?

⟐ Answered janeiro 25, 2021 at 1:53 GMT-7

⟐ Commented janeiro 15, 2021 at 11:37 GMT-7

My question is: to remove it I need a Torx T6 screwdriver with a hollow point or the Torx T6 with a flat tip will work for me. From what I have read, that the hollow point Torx are called Precision Torx or are identified with an "H" after the number in this case: "T6H". The same query is to remove the cover where the WiFi is, should I use a Torx T8 hollow point or does the flat point work for me? From now on I thank you get me out of this doubt, before doing something wrong. Thank you very much and greetings.

Image (Augusto)

⟐ Answered dezembro 23, 2020 at 15:03 GMT-7

⟐ Answered dezembro 11, 2020 at 5:57 GMT-7

I have taken this old Mac mini from my parents house. They goy rid of it because it really was almost unusable and needed to be fixed. It used to start up but it was so slow that any operation was a pain. So I took it, I command + r booted and wiped it.

Than I alt+command + r booted this time but nothing happens now.

I cannot access recovery disk anymore. I cannot do anything.

I tryed resetting pram, no use.

I am sorry I cannot even say how old this Mac is but I guess it should be from 2014 or so.

any help please? It is in really good shape and it would be a pity to throw it away.

Thank you all guys. I could finally install High Sierra via usb pen drive.

it is still damned slow so I’ll swap the old 5400 disk with an Ssd

⟐ Commented dezembro 11, 2020 at 5:40 GMT-7