Replacing my Mac Mini hard drive this weekend, and after following this great walkthrough, I only stumbled on one point – I couldn’t find the fan control wire.
The walkthrough I used, and most others indicated it was located at the front of the machine, but as you can see below, it isn’t there 😦

I did however find a trailing wire stuck to the hard drive which plugged into the SATA interface, I had to remove this to remove the hard drive, and thinking it was just a drive activity indicator, discarded it.
Upon rebuilding the Mac Mini with the new hard drive I find the fan is running full speed constantly. Anyway I suspect then that that wire I discarded may be important, retrieve it from the old hard drive and find that it’s only stuck to the hard drive.
I peel it off and reattach it to the SATA interface, rebuild, and find my Mac Mini back to it’s usual silent self.
The little black plugin, fan control cable, can be seen below, just to the right of the shiny gold SATA cable.

My Mac Mini is a late 2009 model, so I’m guessing they changed the internal architecture quite recently.
I wish I had seen this before – I had the same problem, but the wires came out of the’holder’ itself. The fan is running constantly high, and I think I need to get a new cable! not easy to find…..
OMG!!!!! I can not believe that it took me that long to find the right post. I kept finding older howtos like you found. Now here is the funny thing, my wire was left on there, cause I knew that was a temperature monitor. The problem was, I did not know where it was connected. With your help, I found it, and it was ever so slightly not plugged in. And by ever so slightly, I mean it was still in there, just not pushed up to the very top. grrrr.
Thanks.
Like a fool, I clumsily BROKE that wire and am wondering if you know how to find a replacement connector?
I don’t know, I guess you could try trawling electronics components sites, see if you can find replacement there
I had the same broken connect problem and finally found the part. It corrected the high speed RPM problem.
http://www.gainsaver.com/Catalog/Detail.aspx?&cICode=130330
Thank you for this helpful post. Unfortunately my pins broke when reattaching the cable..not good….
can you take the pictures again; ur pics are focusing on coffee mug & the mouse and nothing is clear on mac mini!!!!
Vik, sorry but that would mean taking it apart again, it’s not much fun as you will no doubt be aware 🙂