This was in a case that had being stored for a while.
It didn't appear have enough power to spin the CPU fan. (although the CPU fan spun up when i plugged in another PSU and also when i plugged the original PSU back in)
But i noticed that the PSU fan wasn't spinning,
So i checked all of the rail voltages, and they were in spec.
Took it out of the case, and all was good, except for the PSU fan not spinning
Heating the thermistor, that's on the secondary heatsink, with a hair dryer, didn't activate the PSU fan.
Plugged PSU back into the motherboard, turned it on, and then it shut down after several minutes (PSU got too hot?).
Now the 5VSB is 6.1V
It's got a TOP222 chip, so i searched for that, and found this:
So, it looks like the chip is probably OK (i checked the cap anyway, and it tested good)
I also checked the standby ouput cap, it has good ESR and capacitance. Tried another capacitor, just in case, but standby is still a steady 6.2V.
I was going to test the TO-92 transistor to see if that was what was causing the fan to not spin, but now have to get the standby running propely first.
Any thoughts as to where to check next?
It didn't appear have enough power to spin the CPU fan. (although the CPU fan spun up when i plugged in another PSU and also when i plugged the original PSU back in)
But i noticed that the PSU fan wasn't spinning,
So i checked all of the rail voltages, and they were in spec.
Took it out of the case, and all was good, except for the PSU fan not spinning
Heating the thermistor, that's on the secondary heatsink, with a hair dryer, didn't activate the PSU fan.
Plugged PSU back into the motherboard, turned it on, and then it shut down after several minutes (PSU got too hot?).
Now the 5VSB is 6.1V
It's got a TOP222 chip, so i searched for that, and found this:
I worked on one psu that had a TOP222. They have an aluminum cap going to the control pin - for frequency or timing. The cap had gone HI ESR, but the 5vsb simply stopped and went to zero. Somewhat of a "critical" cap but does not go overvoltage when failing.
I also checked the standby ouput cap, it has good ESR and capacitance. Tried another capacitor, just in case, but standby is still a steady 6.2V.
I was going to test the TO-92 transistor to see if that was what was causing the fan to not spin, but now have to get the standby running propely first.
Any thoughts as to where to check next?
Comment