ATX_PSU_5VSB_only

[zodiac565]

i got this very new not older than 1-2 years Sharkoon WPM 600 V2
the PSU doesn't turn on testing it with a motherboard+cpu(which work's fine with another PSU), it tries to start and the fans spin not quite a second before it shuts down.
the power supply is very similar to this one tested and carefully documented on this site
https://www.techpowerup.com/reviews/...L650AWT/4.html


i replaced all the cheap Electrolytic capacitor's on the secondary side, near the output rails.

the 'main PWM IC' CM6800TX got 0V on all pins in Power down state, (PS_ON left high).

the 5VSB line showed 5V.
a strange behavior come up when I tried to load the 5VSB line with a 22Ohm resistor (17Watt) the Voltage dropped down to 0.
i see there are small caps around that 'standby PWM controller' TNY177PN
which i guess is responsible for the 5VSB. should i replace these caps too ?.

[CapLeaker]

Re: ATX_PSU_5VSB_only

Try to heat up the caps with a hair dryer, then try to fire it up. See what happens...

[momaka]

Re: ATX_PSU_5VSB_only

the 5VSB line showed 5V.
a strange behavior come up when I tried to load the 5VSB line with a 22Ohm resistor (17Watt) the Voltage dropped down to 0.
i see there are small caps around that 'standby PWM controller' TNY177PN
which i guess is responsible for the 5VSB. should i replace these caps too ?.

Yes, replace all of those small caps. Also make sure to replace the output caps on the 5VSB rail. Both can cause the issues you describe with the 5VSB.

By the way, what brand and series are you using for your replacement capacitors? And where did you get them? (Hopefully NOT eBay!)

[zodiac565]

Re: ATX_PSU_5VSB_only

Try to heat up the caps with a hair dryer, then try to fire it up. See what happens...

Does nothing.

Yes, replace all of those small caps. Also make sure to replace the output caps on the 5VSB rail. Both can cause the issues you describe with the 5VSB.

By the way, what brand and series are you using for your replacement capacitors? And where did you get them? (Hopefully NOT eBay!)

yes i replaced now ALL of the Electrolytic Cap's. and still the same problem.
I replaced them with caps i used to fix other power supplies and now they work again.

i really don't now what part is, faulty. i think some of the SMD parts or the IC's.

i would greatly appreciate professional help.
this PSU got a date on it, its built in 2013.

[stj]

Re: ATX_PSU_5VSB_only

go over that with a magnifying glass - i see lots of cracked solder joints.
hint: HALO's are for Angels - not solder joints!

[zodiac565]

Re: ATX_PSU_5VSB_only

go over that with a magnifying glass - i see lots of cracked solder joints.
hint: HALO's are for Angels - not solder joints!

you mean solder joints that look like HALO's ? can you please give me an example through my picture.

[stj]

Re: ATX_PSU_5VSB_only

i may have missed a few, and some may just be the lighting.
but you get the idea.

[zodiac565]

Re: ATX_PSU_5VSB_only

yea thanks for that tip, i re-soldered some of bad looking solder joints.
what now appears is, when i don't insert one cap of the 5VSB line (the one before the small coil placed on the output side). i get all voltages 3.3V 5.0V 12V when i pull the PS_on Low.

if the cap is inserted still the same problem and no output voltages if PS_on Low.
strange thing.

[stj]

Re: ATX_PSU_5VSB_only

maybe that one cap is bad

[CapLeaker]

Re: ATX_PSU_5VSB_only

yea thanks for that tip, i re-soldered some of bad looking solder joints.
what now appears is, when i don't insert one cap of the 5VSB line (the one before the small coil placed on the output side). i get all voltages 3.3V 5.0V 12V when i pull the PS_on Low.

if the cap is inserted still the same problem and no output voltages if PS_on Low.
strange thing.

Any pictures of that?