Fan issues inside ION

 It might possibly be coming from the CPU fan also. If you absolutely need it fixed ASAP and already have the console open, you can determine if it is the CPU fan by unplugging the cable for it. But don't let it run for more than a few seconds without the fan plugged in or it will overheat the CPU. Now you should know which component is bad, but I would still recommend sending it in to be looked at instead if you aren't familiar with this kind of stuff. It should be covered by warranty if it's less than 2 years old and hasn't been dropped or damaged.

Good luck

: )

 It might possibly be coming from the CPU fan also. If you absolutely need it fixed ASAP and already have the console open, you can determine if it is the CPU fan by unplugging the cable for it. But don't let it run for more than a few seconds without the fan plugged in or it will overheat the CPU. Now you should know which component is bad, but I would still recommend sending it in to be looked at instead if you aren't familiar with this kind of stuff. It should be covered by warranty if it's less than 2 years old and hasn't been dropped or damaged.

Good luck

: )

You should mention that the ION does NOT open up in a very intuitive way!  If you start unscrewing screws, you will be screwed because some screws just want to be loosened and not removed...and some removed and if you do it wrong you wont be happy anymore.

There is documentation for such...but it may not be available to the general public.

Just a thought, the CPU fan probably has variable speed and should change its noise based on CPU load, where the PSU fan is constent.

 I completely agree, disassembling is not user friendly, sorry for the confusion. That's why I mentioned if it was already opened or not. If it isn't open, it can be pretty difficult to tell where the sound is coming from since the vent holes are right next to each other. With the fan spinning faster and hitting something like a cable, then yes it will be louder. But sometimes when the fan bearings start to fail, it can rattle at lower RPMs.

 Also, nobody should leave any of the fans unplugged, even if it's just to get through a show. The CPU has a temp sensor, but I wouldn't trust it to turn off the power before overheating it and doing any permanent damage(probably not covered by warranty).

 So anyway, the console should just be sent in for repair if possible.