68kMLA Classic Interface
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| 6115 PSU stopped working after cleaning | |
| Posted by: erichelgeson on 2020-04-20 12:15:15 Hi all! I am restoring my Performa 6115CD. It had a bad battery so required the double tap to warm start. Ordered some batteries. While I waited I opened it up and saw the PSU was caked in dust. I removed it, opened it, blew it out with compressed air and put it back together. I used some isopropyl alcohol and removed some dust on the motherboard (let it dried for days) - no leaky caps I could see - just lots of dust. Battery arrived, put it in, now it doesn't start at all. Power button seems to do nothing, I hear no HDD, no LEDs, nothing. I have a multimeter but not sure how to start the diagnosis. Saw a few used PSU for ~$30 - though I'd like to repair this. Any thoughts on how to debug this further? Thanks! | |
| Posted by: erichelgeson on 2020-05-21 14:01:16 I believe the fan is getting voltage but not spinning - also there are 2 wires next to the fan's power that loop into a plastic holder and a resistor(?) or something seems to be there. maybe a safety if the fan isnt running? Are there any schematics for this PSU? I cant seem to find them. | |
| Posted by: erichelgeson on 2020-05-23 10:13:46 Here is a photo of the sensor/resistor/xxx  | |
| Posted by: demik on 2020-05-27 15:39:47 Whats the P/N of your PSU ? 61xx ones do not have any power on/off logic or security. Even without a fan they should give power. Did you check the fuse ? Edit : you can check your fan easily. Find another 12V source, and use the red and blacks pins on the fan connector. | |
| Posted by: Nathan on 2020-06-05 13:18:43 I wouldn't necessary rule out sudden failure of some critical PSU component, these machines are 25 years old after all. A multimeter is okay for simple voltage, resistance, and continuity checks, but not generally useful for determining if capacitors are dead (at least not while they're in-circuit) or the overall health. IDK if there are any good test points, but it wouldn't be a bad idea to verify that the inputs/outputs of the regulators seem as expected and that where the electricity enters the board the voltage also seem correct. Also capacitors don't have to look bad or be leaking to be dead/out of spec, or at least that's my understanding. Does it matter whether you leave the battery out or not? P.S. I really doubt it matters here, but compressed air is pretty cold coming out. | |
| Posted by: erichelgeson on 2020-06-16 22:17:24 Thanks for all the comments and suggestions. I traced as much as I could, but I could not find the failure. @JRL sent me an extra PSU they had and I'm back up and running! Thanks! | |
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