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Power Supply Discharging
- Thread starter zoran
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Unplug the iMac, press and hold down the power button for 15-20 seconds, and wait 10-15 min to be safe.
Probably but I'm not familiar enough w/ the internals of this particular PSU to guide you. If the PSU was working w/out issues then being over cautious and waiting an hour or so should suffice. If you suspect the PSU to be faulty, all bets are off.
If it’s faulty and not functioning properly, you can’t trust it to discharge as it should. In this case you need to verify it has discharged.
I guess so. You are in the wrong forum.
The posts about iMac PSU have been available in this forum for years. But since you are expecting to be personally guided on this topic, by answering each and every question you are going to place, I guess you came to a wrong forum.
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Im not expecting any personal guidance.
I haven't found a PSU related thread with what im asking.
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.. but you seem to need someone to Google for you
Capacitor discharge for replacing broken iMac power supply
A friend has offered to give me an iMac (either 2009 0r 2012 model but I haven't seen it close up yet). It works, other than a broken power supply. This ifixit page details the power supply replac...
You said that you want to check that it is fully working in order to be sold.
I don't think that checking for discharged capacitors would be part of that prep for sale...(?)
Typically, removing the power cord, and holding the power button for 15-20 seconds should hasten any discharge.
But, if you can boot up without issue, and the iMac seems to power off when you want it off, then the power circuitry is likely working good enough for you to say that "It works!" --- and caps discharge would not really need to be part of your criteria for deciding that the old iMac is working OK, so you wipe the drive, clean install some system, sell the iMac, and, done...
I suppose you want to check inside the iMac for dust build-up or other kinds of possible problems with foreign material, just inspecting, or maybe providing the possible next owner with a brand new SSD. In that case, you might disassemble enough that you need to remove the power supply... and there's always the good tip to avoid touching the open face of the power supply with your naked fingers. Follow that idea, if you have to remove the power supply for some reason. That's also an extension of the idea that you should treat those connections as if there is a fault in the power supply that prevents the cap discharge.
(You probably don't need to touch the power supply, just to check for cleanliness inside the iMac. Well, unless you suspect there's a problem with the power supply?)
I don't think that checking for discharged capacitors would be part of that prep for sale...(?)
Typically, removing the power cord, and holding the power button for 15-20 seconds should hasten any discharge.
But, if you can boot up without issue, and the iMac seems to power off when you want it off, then the power circuitry is likely working good enough for you to say that "It works!" --- and caps discharge would not really need to be part of your criteria for deciding that the old iMac is working OK, so you wipe the drive, clean install some system, sell the iMac, and, done...
I suppose you want to check inside the iMac for dust build-up or other kinds of possible problems with foreign material, just inspecting, or maybe providing the possible next owner with a brand new SSD. In that case, you might disassemble enough that you need to remove the power supply... and there's always the good tip to avoid touching the open face of the power supply with your naked fingers. Follow that idea, if you have to remove the power supply for some reason. That's also an extension of the idea that you should treat those connections as if there is a fault in the power supply that prevents the cap discharge.
(You probably don't need to touch the power supply, just to check for cleanliness inside the iMac. Well, unless you suspect there's a problem with the power supply?)
Hmm... It's a power supply!
Does your iMac boot without issues for you?
Do you have any problems with any external devices?
Do you have any problems doing tasks that your iMac might do for you?
Is this an iMac that you purchased new, so you know the history of this iMac?
Do you need to open up your iMac to check for any accumulation of dust inside?
Finally, if you want to sell this iMac, a good way to test most everything inside, (including the power supply) would be to boot to an installer, wipe the drive, and install fresh system. Shut it off when you get to a screen for new user setup. Leave it ready for the next owner.
Does your iMac boot without issues for you?
Do you have any problems with any external devices?
Do you have any problems doing tasks that your iMac might do for you?
Is this an iMac that you purchased new, so you know the history of this iMac?
Do you need to open up your iMac to check for any accumulation of dust inside?
Finally, if you want to sell this iMac, a good way to test most everything inside, (including the power supply) would be to boot to an installer, wipe the drive, and install fresh system. Shut it off when you get to a screen for new user setup. Leave it ready for the next owner.
I’ve had changed grfx card once with a second hand one that failed after a few months.
I had cleaned all the dust back then.
Now the iMac is left on the side, its not worth getting a new grfx card, so I purchased a mbp and im working with that.
Regarding its great 2K LG display i’m interested in making the 27" iMac a standalone display, so i purchased a Chinese controller board which has its brightness issues.
I guess I might wait for a JuicyCrumbs board to be released. It will prolly take long so if i cant wait, I will strip all its interior hardware and sell it.
That’s my iMac story. 🙂
I had cleaned all the dust back then.
Now the iMac is left on the side, its not worth getting a new grfx card, so I purchased a mbp and im working with that.
Regarding its great 2K LG display i’m interested in making the 27" iMac a standalone display, so i purchased a Chinese controller board which has its brightness issues.
I guess I might wait for a JuicyCrumbs board to be released. It will prolly take long so if i cant wait, I will strip all its interior hardware and sell it.
That’s my iMac story. 🙂
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