Fan Not Working Issue..any Help?, hardware problem Options

[cyrross]

had an over heat issue...had recently changed out stock fan for a Talismoon LED..after putting in this fan I noted the left side (CPU) was not functioning and ended up with an overheat issue (2 red lights) replaced the original stock fan and the stock fan's right side (GPU) is now not working...again cuasing an overheat issue.

is there a way to test the fans independantly to see if they are bad and the problem is on the board? if it is the board, why would a different side be out for each fan? Rather odd that both fans go downa t the same time.

I have also already completed an Xclamp replacement while my fans are down, since I had the box open already. Works fine except the fans.

Please if anyone has any solutions it would be much appreciated

[RDC]

The fans are probably just wired different from each other, hence one is 'bad' on the Talismoon and the other is 'bad' on the stock set.

What you do NOT want to do is power both from the same side, if that idea crossed you mind, you'll just make it worse. One of the Transistors that controls the fan has gone bad. Were you powering anything else from the fan header there as well?

There is a Transistor tat will blow if too much current is drawn or something happens. There is one for each fan and you're problem isn't really that uncommon.

You have a couple of options here, either replace the Transistor, Q3A2 (top of board at the fan header, for GPU side fan) or Q3M1 (bottom of board at the fan header, for CPU side fan). If that's not withing your scope get someone to do it, or you can just hack the + wires from the plug and wire them to a straight voltage source (Red and Brown wires are + on the stock fan), either 5v or 12v. The Ground wires, Blue and Black, can stay in the plug and plugged into the header. If you want them to run at 7v then you'd cut the Ground wires from the plug and connect them to a 5v source while the + wires went to a 12v source.

The thing with wiring them to a straight 5v, 7v or 12v source is you loose the Thermal control over them, but running them at either 7v or 12v (if you can stand the noise at 12v) doesn't really require it since they're moving more air and the 360 will stay cooler from just that. Replacing the Transistor will return it to how it worked before.

[Robotboy1]

Or you can wire them to a rheostat and get a knob so you can control the fans like i did.

[cyrross]

I have not done anything like replacing a transitor, however, I'm sure I can do it..is it just a matter of getter the transitors and sodering them to ther board or is there more to it?

Also, are there special ones for for the 360 or can I just find the type note (Q-something or other) on the internet and it will work fine? Lastly how to tell which is the blown transitor as each fan has a different side out ? (I'll assume use the stock fans side to determine, but want to be sure)

You called it, had put some lighting in when I first put in the talismoon fan, but one wire had a spice in it and did not work right so I pulled it and tossed it. Seen any tutorials on adding a transitor for this or should I just wing it?

[RDC]

Like I said, the fans are probably wired different from each other, hence why one is dead on the Talismoon set, and the other is dead on the stock set. Go by how the stock fans are acting and replace that Transistor and you should be alright

The Transistor is either a ZT751 or a BCP51, either one will work as a replacement and it needs to be one of those. There are a slew of others that would also work, but I'm not gonna get into that mess. The Transistor is Surface Mount and there are a lot of other really small SMT parts around them as well, so if you don't know what you're doing, have someone that does do it for you, the last thing you want to do is go lifting traces and removing parts 'accidentally' that don't need to be removed and making a bigger mess than it's already in.