CPU FAN: on which cable should I solder a resistor

nouxtywe

macrumors newbie
Original poster
Jan 6, 2014
10
0
Hi guys,
Could an expert give me some advice about how to solder a resistor to the alimentation of my CPU Fan?
Because I have the exact same problem of this guy :
http://forums.macrumors.com/showthread.php?p=18598028#post18598028

Cpu fan @ Max speed but SMC displaying 0 rpm.

I'm gonna do it, but I kinda need some more intel because I don't want to screw everything up :)
A photography or a technical sheet would be the best... but I'm dreaming I guess :)

Here's the piece of the iMac (from ifixit)






Thanks for your help!
 

thejadedmonkey

macrumors G3
May 28, 2005
8,065
804
Pennsylvania
My guess is that you can put the 100ohm resister on either wire, and it will sufficiently slow down the fan speed. It won't sound like a jet engine, but remember it will also prevent the fan from ever going any faster than that speed, which could cause overheating.

But yes, either the black of white wire. It shouldn't matter if it's on the ground or powered line.
 

nouxtywe

macrumors newbie
Original poster
Jan 6, 2014
10
0
Hi,
First, thanks a lot for your interest and your comment :)
Can you assure me that those 2 wires I pointed on the last pick are the powered line?

Thanks again :)

So it would be the cable #2 on those pics, right?

 
Last edited:

BJonson

macrumors 6502a
Aug 26, 2010
833
113
You have to short the hard drive temperature sensor. I stuck a wire inti both holes connecting them. That stops the fan from going nuts and keeps it at 1100 rpm. It's not the CPU fan but the hard drive fan.
 
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