I see that this is becoming an old post but I wanted to add some testing that I’ve been doing on a 2011 Mac mini that was given to me. It exhibited exactly the same symptoms as other here are experiencing where the computer power indicator (sleep indicator?) comes on only for a brief moment when the the power switch is pressed. I’ve been working on this on and off for about 4 months… not wanting to give in.
I also noticed that as the unit was plugged in, the power indicator would flash momentarily even without pressing the power button. Other Mac Minis that I have do not do this. I did a number of tests looking for shorts and other irregularities on the logic board but found nothing. In the back of my mind, the GPU issue of the 2011 MacBook Pro was always present. And, there was a similarity with this and the HP G62 which suffered a similar fate. The computer would not start, but the caps-lock would flash.
I decided to add some solder past and do a reflow of the AMD GPU. At this point I really had nothing to lose because it didn’t work anyway. I applied almost 500 degrees Fahrenheit for 2.5 minutes using a rotating motion of a SMD station. After letting it cool down, I plugged in the Mac mini and the power indicator did not flash this time. Next,I pressed the power button and the computer immediately started up. It ran long enough for me to do a full installation of High Sierra. I let it run for a while and after some undetermined amount of time, the computer shut down on its own.
I was able to start it up again but I found it to be unreliable as it would crash and restart while trying to start up.
To sum this up, it appears clear to me that the reason so many of these 2011 models were no longer starting up was due to the failed AMD GPU. Of course, what I’ve done in no way is a fix. We all know that these GPUs cannot be repaired, but it appears to me that the GPU is the reason for the failure.
I challenge others that have the opportunity to do this same test, do so, and come back with your results.
Hi Barry, i am having the exact same issue. Did replacing the power supply fix your issue?
Aaron
- de Aaron Burton
Hi, i am having the same issue as well. I check the power supply and it is working with 12 v, and I check the battery and it has the nominal 3v. Any additional ideas? I think it could be a motherboard problem, but no idea how to check nothing there.
Regards,
Javier.
- de Javier G.Pazos
I found this, but doesnt work for me yet.
OK, just in case someone has the same problem in future. I left the mini in the hands of a tech guy who couldn't figure it out. But then, someone on Apple discussions pointed out how to solve this issue.
Basically you leave it unplugged for a night, plugged in it, press cmd + alt + p + r along with the power button of the Mac mini.
Now, this might not work right away. If it doesn't work right away, unplugged it from the wall again, leave it for 5 min, then plugged it back in and try it again.
The person who mentioned this said it took 4 days and over 200 tries before it turned back on. For me, it took 2 tries and it worked.
This is also why it happens:
The EFI firmware on the pram has been corrupted and the instruction to start the computer is not being properly executed. EFI firmware is the same as the BIOS on a windows machine
Kuddos to Lemas. All credit goes to that user
- de yuri.tasso