tattar8 Posted February 1, 2020 Report Share Posted February 1, 2020 So I've got my hands on a dead IIci, that came seriously dusty, and with a Maxell bomb having just gone off, but recently enough to be fixable (no rotten traces). While I wait for the replacement caps to come in, I thought I'd turn my attention to the PSU. First thing I did was probe pin 10 to see if it was live, and I got +5V off it, which I took as a good sign. Then I shorted it to pin 9, which should power on the PSU, but no dice there -- no fan, and no voltage on the main +5V rail. I'm thinking this has to do with the capacitors inside. Is there anything else I need to look out for? And before I begin, do I need to do anything to discharge the caps? Quote Link to post Share on other sites
tjjq44 Posted February 1, 2020 Report Share Posted February 1, 2020 When you short pin 9 and 10 you should hear a "click click" sound. It's the relay inside the PSU which toggles power to the secondary AC outlet. The reason why it's clicking is because the PSU isn't "loaded" and safety circuit prevent it from starting for good. On the other hand, if you don't hear this little clicking noise, your PSU may have a problem... Quote Link to post Share on other sites
tjjq44 Posted February 1, 2020 Report Share Posted February 1, 2020 The electrolytic caps inside the PSU don't necessarily need to be replaced but the "X" and "Y" filtering caps can safely be removed... they often explode inside! Quote Link to post Share on other sites
Compgeke Posted February 1, 2020 Report Share Posted February 1, 2020 The electrolytic inside these absolutely do need replaced. They also leak out onto the board but don’t cause nearly as much damage. Easy fix though - they aren’t surface mount. Quote Link to post Share on other sites
tattar8 Posted February 2, 2020 Author Report Share Posted February 2, 2020 Alright, I ordered all the caps I will need (cost me less than $10 including the huge ones). I didn't really listen for the click, but then again, I wasn't really listening for it. If the relay was clicking, then wouldn't that imply that I should be seeing voltage on the 5V rail, even for just a little bit, since the relay appears to be connected straight to it? Does anyone have a schematic for this thing? Quote Link to post Share on other sites
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