5 Replies Latest reply: Jul 8, 2014 4:38 PM by tbirdvet
MarcoStreet86 Level 1 (0 points)

Hello everyone, this is the first time I write in support apple. I'm an Apple user for many years and working in the world of computing.
I am a specialist in repairs Hardware and Software on Laptops and PC.

Personally, I use a Mac Mini A1176 mid-2007 CPU with 1.83 ghz intel core 2 duo.

A few days ago while the Mac is off, and also holds on to the CPU fan is at 8000 rpm.

I tried to reset the SMC but the problem persists.

I disassembled the mac and I replaced the fan with another purchased from a dealer, but the problem persists.

My mac has the version of Boot ROM Version MM21.009A.B00 and SMC 1.19f2.

you can have a firmware reset CD for this model?

I also made diagnostic tests and I was presented the following error:

4MOT/1/40000003 Masters - 8363

What can I do? Have you ever?


Mac mini, Mac OS X (10.7.5)
  • lllaass Level 10 (175,658 points)


    http://www.macissues.com/2014/03/21/how-to-run-and-interpret-apples-hardware-tes ts-on-your-mac/

    4MOT: Fan motor

    Assuming the dealer fan was good, it would appear you have a problem with the logic board.

  • MarcoStreet86 Level 1 (0 points)

    Thank you for your response.

    I think the fan vendor is good. I also thought it was a problem on the logic board, but I think it's software (SMC etc.) and non-physical.


    Is there a way to rewrite the SMC firmware?

  • lllaass Level 10 (175,658 points)

    Yes, the SMC can be updated just like the EFI.

    Apple only released, for the Mini, SMC updates for both 2006 Mini's


  • MarcoStreet86 Level 1 (0 points)

    Hello, thank you for your help. But I had to solve in a completely different way. Unfortunately, the page proposal was no longer offering the SMC for my mac mini. I checked out other possible solutions on the net, but none have solved the problem.

    So, despite not being a big electronic, I took a soldering iron, scissors and a trimmer and I made a manual change to the mac mini for reuse without hearing his fan at 8000 rpm.

    First of all I removed the fan from the mac mini.

    I cut the wires and I have identified the positive terminal, speed sensor, and the negative pole. To do this I used a 12V battery. With a resistance of 30 ohms I tried to feed it. (I wanted to use a resistor to avoid burning the fan by reversing the poles).

    Once you have found the poles I bought on ebay the following product:


    I cut the wires to the input voltage and have them welded to the cable connector on the logic board, and in the end I soldered the output cables to the fan.
    Now finally straightedge speed from 3170rpm to 8000 rpm and the temperature at minimum speed with little load is 50 °.
    The trimmer zalman warms up a little, but for me it is the best solution to continue to use my mac mini.
    Unfortunately, the problem of my fan was definitely a hardware problem on the logic board.
    Thanks for your help and I hope that my solution can also serve to others with the same problem.



    After this operation is a day that the mac mini is running without any problems


    Sorry for my English by google ..







  • tbirdvet Level 4 (2,880 points)

    I'm impressed.  Good job!