Hi my PSU(CM GX 650W) was giving me some problems and i ended opening up (it has no warranty, i dont live in USA) and i found something burned (?)

Seems like i can replace those elements but i need to know if that is possible and what kind of elements are those two.

Thank you.

 

Was it from a Cooler Master PSU like this?


What experience and tools do you have with electronics? Do you have a hot air desoldering gun and multi-meter?

It would be tough for me to repair this type of power supply...

Allen

 

These 2 parts are a resistor and a diode.
But without a schematic it would be prettey hard to replace them due to the reason, that there are no specs of the diode and it seems like the number on the resistor is scrached away... but even if know the specs its tough, there could be much more wrong with the psu except these parts...

BTW, are these faulty parts on the HV or LV side of the PSU?

Nikan

 

Was it from a Cooler Master PSU like this?

View attachment 125348
What experience and tools do you have with electronics? Do you have a hot air desoldering gun and multi-meter?

It would be tough for me to repair this type of power supply...

Allen

Yes it looks like that, its a Cooler Master GX 650W 80+ white. I have both tools, dunno if replacing capacitors in a TV and fixing/soldering my toys is enough experience

These 2 parts are a resistor and a diode.
But without a schematic it would be prettey hard to replace them due to the reason, that there are no specs of the diode and it seems like the number on the resistor is scrached away... but even if know the specs its tough, there could be much more wrong with the psu except these parts...

BTW, are these faulty parts on the HV or LV side of the PSU?

Nikan

I was doing some research the little one is called Resistor SMD and as you say the code is gone, the diode looks like it is the same as D19 and D18 with a tiny white line.
Well the PSU works but the fails randomly. there are more components in the other side but the cables dont let me see.
What do you mean with HV and LV side?
I can other PSU but i really would like to fix this and if there is a chance my wallet would be happy. But it's really frustrating that because of (possibly only) these 2 elements i have spend more money.

 

well smd parts especially resistors are pretty cheap we are talking about 2 cents for a smd resistor of that size it looks like a 0805 size to me...
I meant if its one the high or low voltage side of the PSU... du you have test equipmint on hand??

 

Do you know how to read schematics?

This is a typical SMPS PSU circuit diagram...



The parts covered in the green box is the Low Voltage area and the rest of the components outside the green box is the High Voltage Area.

Allen

 

Do you have experience with SMPS's?

 

I see that there is a suspected dry joint in your PCB. May be you can apply some fresh solder and re-solder it. It might be the cause of your intermittent fault..


note: 780K jpg file

Allen

 

well even if we know the resistor value we still dont know what d14 is and caused this falure...

 

No, i don't any experience with SMPS but i can learn. I can read schematics but that looks a bit complex, i recognize some elements.

 

well i wouldn't suggest poking around on a device working on live mains...
its not that healthy

you said that it works sometimes...

it could be anything... a bad solder joint, a bad functioning feed back loop, it could be a timing cap etc etc

 

I see that there is a suspected dry joint in your PCB. May be you can apply some fresh solder and re-solder it. It might be the cause of your intermittent fault..

View attachment 125357
note: 780K jpg file

Allen

YES, it says 470 the code its still there but its a bit brown, ill resold the dryed one. Im still not sure how to recognize if it is in the in HV or LV since its a PCB is attached to a larger PCB.

 

well i wouldn't suggest poking around on a device working on live mains...
its not that healthy

you said that it works sometimes...

it could be anything... a bad solder joint, a bad functioning feed back loop, it could be a timing cap etc etc

yes but i can try with those visible problems first, if that fix it ill be ok with that. I know its risky but knowing that i can fix it excites me.

 

I extracted the SMD resistor and the multimeter says 47 ohm which is the correct resistance according to the code (470) apparently it is ok ?? I think its 0805.

 

I only need a Diode now, dont know if its a SMD Diode, there are 3 diodes that looks the same but im not sure can if they have the same values.