Help and Advice on Repairing PSU

[arkevius]

Hey all,

I have a Corsair HX620W Modular Power Supply.
It was working fine until one day I rebooted my computer, but it would not reboot. The fans would kick in for about a second, then would die. Upon testing the PSU, I was getting about a second of fully power output, but then it could die, only leaving the +5VSB. In fact, the +5VSB is detected even with the PSU off and not turned on (being jumped either by the motherboard or shorting the pins, not the switch on the back).

Does anyone have a clue as to what may be causing this? Upon inspection, all the caps are good; no bulge, no leaks. I'm not experienced with testing individual components, but if someone could point me in the right direction I'm more than eager to learn and get this thing fixed.

(I actually got another PSU for my computer, so that's not the problem. I'm just bound and determined to fix this thing and not just throw it away).

 

[nvalhalla]

the 5VSB should always be there, that is normal. Fixing the PSU though... Do you really like soldering?

 

[arkevius]

Oh, well on another PSU I tested to compare the +5VSB wasn't there. *confused*

I'm new to soldering, but I'm willing to do what's needed to fix this PSU. It's become my little project. I need and want to learn how to solder anyways. Being a tech, it would be beneficial for me in the end.

 

[nvalhalla]

that is odd. The 5 Volt Stand By is there as long as the PSU is plugged in and the switch is on. It is the power needed for things like Wake on LAN and stuff.

First thing you need is a print out of the 24 pin ATX and it's functions. Short the pins to turn it on for that second and start measuring voltages. Makes sure nothing else is connected to the PSU, it should be out of the case.

If I had to guess at the problem, you are shorting somewhere in the PSU and the protection fault is tripping. Does it allow you to turn it on again without flipping the switch or unplugging it?

 

[arkevius]

Power Switch ON, not jumped: Only getting the purple +5VSB
Power Switch ON, jumped (fan sputters, then dies): purple +5VSB, both yellow cables showing +1V (caps?)
Power Switch OFF, not jumped: green cable ~2.4V, purple cable +0.5V
Power Switch OFF, jumped: +1.4VSB, both yellow cables show +0.3V (caps?)

Trying to jump the PSU again without using the power switch or re-plugging the power cable results in the fan spinning up and dying again.

 

[arkevius]

Oh, and I went ahead and took out the actual PSU from it's incasing as best as I could, placing it on a piece of cardboard. Should be a bit easier to get at the components then, no?

Thank you for helping me with this too btw, it's much appreciated.

 

[arkevius]

Any takers on this...?

 

[Proximon]

I'm putting a stop to this thread. Working on a PSU is dangerous and should only be done by those with adequate training in such things. A PSU can hold a LETHAL charge long after it has been unplugged from the wall.

This is an inappropriate forum for this discussion.

 

[Proximon]

This topic has been closed by Proximon