G5 20" iMac Power Supply Issues Again!

Well, both of our old G5 iMacs have had the logic boards replaced under the extension repair program. Also one of of them had the PSU replaced as well under the same program. Well, now the other one has gone south. I pulled the power supply out and it had several bulging capacitors so I replaced them. However, I also noticed that there is a fried surface mount transistor right next to position R4 on the under side of the board. I've replaced the caps but I can't figure out the values of the fried transistor. I've taken some pics of it. I'm really hoping to track down the part and fix it myself. However, if not, might anyone have a replacement PSU for this 20" imac or know where I can get one inexpensively?
2nd question:
I went though the process of a service agreement on the Apple site. I entered the problems and got to the final page and it quoted me $74.95. However, I'm not sure what this charge is for. Do I ship the entire iMac in? or is this for a replacement PSU? I'd really like to make a trip to the Apple Store but we're stuck at home with a newborn for the next several days.
Anyway, any information would be great.
Thanks much,
Robet
Message was edited by: RRack

Hey Robet,
service agreement on the Apple site. I entered the problems and got to the final page and it quoted me $74.95
Hmm but you wouldn't have a service agreement on this machine. Call as DaddyPaycheck suggests.
I also noticed that there is a fried surface mount transistor right next to position R4 on the under side of the board. I've replaced the caps but I can't figure out the values of the fried transistor.
Wow you must be pretty good to want to try to replace that SMT transistor! I'd be afraid that there would be other damage as well: diodes, power ics, switch mode chips etc. I've got 4 G5 supplies here and only one worked after the cap swap. I didn't feel trouble shooting the entire supply was worth the time.
What I've done is more on the lines of this:
http://gallery.me.com/iamkimc#100033
Actually any ATX (non Dell) supply will work.
I extract 2 12V leads from the hard drive power plug using a pin extractor like here:
http://www.amazon.com/gp/product/B001KQDS6G
I bought this but so far only use the top one. It works well. If you're only doing a few you can use some of the tricks here:
http://www.xtremesystems.org/forums/archive/index.php/t-88644.html
If you look at the iMac G5 ALS pinout:
http://www.xlr8yourmac.com/images/imacg5power_supplypinout.gif
and compare it to the 20 pin ATX:
http://www.subedartech.net/docs/pc/connectoratxpinout.GIF
On the right you see that the difference in the first 20 pins is: Pin 12 -12 VDC and Pin 18 - 5VDC. So I extract those two pins clip them off. Shrink tube the ends and replace them w/ 2 yellow leads (+12VDC) that I extract from the hard drive leads. Once cleanly extracted they just push and lock in place.
Note that pins 11 (black, ground) and 22 (Brown + 24VDC) are not covered. If you have the early ALS you don't need these two leads (go figure) but if you have the later or 20" you need a separate supply for those leads. I use a old 24VDC PowerBook supply for that. Model M7783 it puts out 24VDC at 1.0A.
It's kind of messy but all the parts fit behind the iMac and aren't seen.
Also it seems like you're watching your pennies w/ the new baby. (been there)
we're stuck at home with a newborn for the next several days
More like months with us.
Good luck and I hope you're sleeping.
Richard

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1st Gen iMac Power Supply Issue

I just got my iMac G5 back from Apple after having the power supply and logic board replaced for the second time in two years.
It is apparently a fairly common problem with the first generation iMac G5s. I've basically been told it's a problem with no real solution and that they'll fix it for free (for the first three years). It's great that I'm within the three years, but if it happens again after October, I'm likely going to have to foot the bill to get it repaired.
Does anyone have any more detailed info on this issue (other than Apple's Repair Extension doc)? Would turning off the computer each night prolong the life of those parts? Would turning it on/off everyday reduce the life of those parts?
Any thoughts/comments?
Thnx...CN
iMac G5 Mac OS X (10.3.9)
iMac G5

Just to add to BB's comments, I doubt that leaving the computer on will have any benefit at all for you in terms of longevity. If you have problems with faulty capacitors , and the like, in fact it will probably make the issue worse rather than better (though I doubt this will be a problem for you if your logic board was replaced after about April 2005). Doing so will probably also add a little extra wear to the bearings of your HD (unless you have it set to spin down when not needed) , and will cost you a little more (but not a whole lot - though when we all leave them running the environmental costs continue to mount) in electricity over time.
You should probably also shut down every so often anyway - maybe once a week or so, to help clear some potential memory issues that can persist with some applications even under OSX, and you should certainly shut down at and start up again at any time when you notice slowdowns, program "hangs" or other problems.
Cheers
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Heat, and Fans, and a Power Supply issue! Oh, My!

Hello,
My iMac G5 2Ghz (20") has been experiencing issues lately which I thought were resolved back when I brought it in for the "Repair Extension Program for Power Supply Issues". I took it to my local Apple Store and they replaced the power supply as well as my HD. The machine kept shutting off at random times as well as heating up, so it broke my HD after several months making me forced to bring it in. First and most importantly, the machine is producing a significant amount of heat which I believe is not normal, especially when doing simple tasks such as opening a file or folder on the desktop just after boot. I don't mean to complain about the heat, but the whole room is filled with hot air and it feels like somebody turned the heat on. I have several other Macs around my house and no two of them make as much heat as this one. (iMac G4 and eMac G4) The fans power on from time to time, but "rev up" when doing CPU intensive tasks. I understand the fans need to be at a higher speed, but they were never this high when I just used iMovie back in 2005 when this was new. Now, I know others have been having issues in these related areas as well, but is there anything else I can do. I have tried about everything, but I am just worried that power supply and HD will go again. Also, the highest inside temperature I recorded was "161.4°F". I thought that the normal temperature was "70°F", so if anyone could tell me that as well, it would be appreciated.
I have tried just about everything:
PMU/SMU reset
PRAM reset
reset-all
repair permissions
You name it, but fell free to reply with something new. (the fans are already clean)
Thank you.

Thanks for the reply. I at one point ran the hardware test using my installer disc and all was fine. It seems that the fans were actually running better when I booted from the disc which leads me to think it could really be partially a software issue. There is a possibility there is something corrupt in the system files, but I had to reinstall Mac OS X a few times due to them replacing my HD. It seems the computer runs cool with the lower versions of 10.4, but warmer with the higher versions of 10.4. It now makes sense because it shipped with a lower version and over time got worse with the higher versions. I am assuming that the people who got their power supplies replaced had the lasted update possible causing this issue. I cannot be 100% that it is software because I do not know exactly which system files run each hardware component. I am currently using the machine a lot and would not be too happy without it for about a week. (although, before the holidays come it may be best to bring it in before the holiday gift repair parade comes in!) Thanks again for the advice and if anyone owns this machine, feel free to share your message.

My Time Capsule has just failed, 2 months after the end of 12m warranty. same old known power supply issue, "just unlucky" says my local Apple service center. ***?

i bought a 2TB Time Capsule in Sep 2010. its just failed last week, less than 2 months after the expiry of the 12month warranty.
and 3 months after the end of Apple's offer to replace all the many Time Capsules that have failed previously due to this same fault.
nice timing guys.
"yeah, its dead. same old known power supply issue", says my local Apple service center, "just unlucky".
huh? "unlucky"? you sell products with known defects, and when it fails i'm "unlucky". nice.
"OK, anyway, how much to fix it ?", i ask.
"you can't fix them, its closed", is the reply, "you have to buy another one".
"hmpf. OK, how do I get my backed-up data off it ?"
"you can't. we could try break it open and recover the hard disk i guess, but no guarantees we'd get it, and you'd have to pay for us to do that, whether it works or not of course".
"er.... is there a hidden camera in here? are we on TV? you can't be serious ? ..and this piece of garbage is what i've been using for a secure backup of my precious, irreplaceable, priceless personal data ???"

ceeb28744. Welcome to the Apple Users Support Community. Sorry to hear your TC died! You said it was a 2TB so I would guess it be the model A1355/MB997LL/A or MC344LL/A. Believe it or not all users of these time capsules will eventually experience this problem like you have. There is a 99.5% (or better) chance that the only thing that is wrong with it is the internal power supply. If you will go to this site.... https://sites.google.com/site/lapastenague/a-deconstruction-of-routers-and-modem s/apple-time-capsule-repair and once there look over at the left side and you will find:
Apple Time Capsule Repairers and from that list you will be able to choose from a list of individuals that could repair your TC and have it returned to you fully operational again. The individuals on the list are hardware technicians and they can save you a lot of money and time.
Larry

G5 Powermac Dual Core Power Supply Issue

My G5 Dual Core 2.3 GHz was working fine till this morning when at about 6:00 AM the power supply started making a bunch of noise. Luckily I was at home not at work so I pulled the plug...waited a while, powered on again, saw the apple logo and decided to turn it off till I get it fixed.
This is the third G5 I have with power supply issues. The first one was a dual processor that hums when doing a lot of networking or when attaching USB flash drives...so apparently there was a extension program on that one. I sold that and switched to the dual core machine, then both of the dual cores had power supply issues. One got replaced under Apple Care. The 3rd one just had the issue happen.
Anybody having bad luck with these? My old G4 DP 1.42 has been running almost flawlessly since it came out (only replaced the main fan for a more powerful and quieter unit).
Have the power supplies for the Dual Core G5 machines been redesigned or should I expect my new one to fail again?

Hi Jack,
I'm sorry. You did note that with your first G5 you knew of the extension program. Too early in the day for me I guess. Personally I haven't sensed from the G5 discussions that Power Supplies have been a major continuing issue, but there certainly have been a lot reported. Usually it's Logic Boards that keep getting fried for one reason or another. Fortunately it doesn't seem to be the most expensive thing to replace, especially if you buy a used one. Maybe someone will chime in who is more observant then I am this morning.
For what it's worth I still have the first Mac I ever bought which is a PM8500. It still runs fine whenever I pull it out from it's dusty storage. By contrast this is my third G5.
Edit: Up early and fasting for a test... I just caught your reference to 3 years. That time frame I have seen a lot here, usually 3 years plus a few months, just out of Applecare. Apparently for G5s thats like 90 in Mac years.
Message was edited by: Samsara

MDD power supply issues

Good evening.
There seem to be more frequent power supply issues with the MDD than with other models of G4 desktops.
Is there a reason for this?
Thanks for your time.

Hi Glen-
I see more Power Supply failure postings here than on any other Older Mac discussion. I think the accommodations made for heat are simply not enough for these hot dual-processor Macs.
The huge processor fan keeps the processor module from melting, but does not effectively dispose of all of that hot air. Some of It filters up through the cabinet and the PCI slot cards add even more. The perforated slot covers allow a little air movement, but not enough to release the heat generated. Any hot air that makes it to the top of the case gets sucked out through the power supply -- and that cannot be doing it any favors.
In contemplating adding a Core-Image qualified display card, I took a hard look at adding a hot display card (that requires an additional power connector) to the SCSI card already in place, and decided more cooling was in order. I am currently experimenting with a thermistor-controlled slot fan (up to 45 cfm) exhausting out through the top slot, with its inlet facing UP, and all solid slot covers in place of any remaining perforated ones.
My first measurement of exit temperatures showed the air coming out the slot cooler was almost ten degrees cooler than the power supply exit air, so I think I am doing something. Whether it is enough to run all this hot gear without cooking the power supply remains to be seen.
I do not think it is an accident that when the dual G5 cabinets were designed, processor control of multiple flow-through cooling zones was the way they chose to make it work. I think the whole dual G4 cabinet got so hot inside the engineers were caught off-guard, and had to resort to drastic measures to keep G5s from dying (like the MDD G4 did). Then Steve announces that he can't take the heat (for the processing power available) and Apple will switch to Intel (because they are so cool).

Imac keeps shutting down - is this a power supply issue

Dear all. Help would be much appreciated.
my imac G5 has recently started shutting down by itself - always about 1 minute after starting up... I have seen a few suggestions to reset the PRAM and the power switch - both of which I have done to no avail.
I have hoovered the dust out - still same problem.
Question is - can I be confident that this IS the issue - and order a replacement part?
I would like to install it myself - thus avoiding cost for a repair - and am confident I could do it if I had good instructiuons.
Can anyone help me with my diagnosis or how to fit a new power supply?
Thanks in advance - I am really missing my imac!

You can't be completely sure that it's the power supply, it could be bad caps . Open the machine up and inspect the caps, and also the ones in the power supply unit. If any of them is bulging or leaking, that would be your problem. Look at http://www.jimwarholic.com/2008/07/how-to-repair-apple-imac-g5.php for instructions and help.
You can also try to run Apple Hardware test from your install disk and see if it comes up with anything, also, from your install disc try to run Disk Utility:
1. Insert the Mac OS X Install disc that came with your computer, then restart the computer while holding the C key.
2. When your computer finishes starting up from the disc, choose Disk Utility from the Installer menu. (In Mac OS X 10.4 or later, you must select your language first.)
Important: Do not click Continue in the first screen of the Installer. If you do, you must restart from the disc again to access Disk Utility.
3. Click the First Aid tab.
4. Click the disclosure triangle to the left of the hard drive icon to display the names of your hard disk volumes and partitions.
5. Select your Mac OS X volume.
6. Click Repair. Disk Utility checks and repairs the disk.

IMac 233 power supply issue

My bondi iMac died several years ago and I've been trying to resurrect it. The AV board was replaced professionally some time back and everything was great until it abruptly would not start. I just replaced the power supply board but all I get is a persistent ticking sound. After mucking around a bit I discovered that if I unplugged the grey cable bundle (with one blue wire) from the power supply board at P908, which connects to the AV board at P505, the computer boots normally but without video. Can anyone identify this cable? Can it go bad? I've tried every suggestion from every forum but nothing else has any impact whatsoever, just tick tick tick....I know I could probably connect an external monitor but I don't have an old one or an adaptor. Besides, that solution lacks elegance. It's too pretty to stick in a beige box.
I love this computer and hate to trash it, so thanks to anyone who can help!

My guess is that it is not a problem with the cable. The problem may be that the power supply board is becoming faulty (weaker). Therefore, when it is not powering up the video subsystem (which probably draws at least half the overall power), the power supply is able to power the rest of the system.
It is also possible that the PAV board has gone bad for the second time. That would explain why it does not work when it is connected. Quite possible. Even replacement parts are old, and even if was not previously used.
Fortunately, it seems like you know how to take that iMac apart all the away, which is not easy (be careful with the high voltage in the backside of the CRT - it's there even when the iMac is disconnected). If the problem is the power supply board, they usually do not go bad, so it should be possible to find a good replacement on eBay or elsewhere. If the problem is the PAV board again, you know the deal...

Intel iMac Power / Overheat issue?

Hi there,
I have an Intel iMac from 2006. About 2 years ago it started to just turn itself off randomly as if there was a power failure. When it does, the only way to power it back up is to switch it off at the plug, switch it back on and press the power button (strangely) twice. I have noticed it seems to be temperature related - when my iMac reaches around 78C (which I'm pretty sure it should be able to handle fine?) it tends to be in the danger zone and at any minute can switch itself off.
I've got around this by using smcFan Control - which thankfully displays the temperature in the menu bar meaning when I hit around 72C I can whack the fans up to full blast to keep the temperature down. Being a sound studio computer - the hum of the fans really isn't ideal, but it at least makes my computer usable. However, I'm currently in the middle of a big project on Logic and I've had to turn my room into a fridge (window open-more clothes on) to be able to work on it as all the processing involved heats it up to 75C+ in no time.
I was hoping someone could shed some light on this or at least tell me if I am right in thinking that 78C is nothing really and the iMac should deal with it easily.
I have seen tons of posts regarding the G5 iMac power problems and similar problems with the intel iMacs - I've done all the hardware resets (PRAM, SMC, PMU) as suggested in these forums but nothing has helped.
I have had the power supply changed in the past (before this problem arose) as one day it just went kaput. Don't know if that makes any difference but I'm pretty sure that the problem started a little while after the replacement was installed.
Thanks in advance!
Message was edited by: Lee_Head

LR is a Universal Binary app. YOu're good to go. I did a migration from iBook to MacBook recently with no issues.
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Don Ricklin, MacBook 1.83Ghz Duo 2 Core running 10.4.9 & Win XP, Pentax *ist D
http://donricklin.blogspot.com/

Are 2009/2011 iMac power supply compatible with mid2010 iMac?

I have a mid-2010 that doesn't turn on. None of the LEDs turn on and I've been troubleshooting for a couple weeks with no luck. I want to buy a power supply for the iMac but I'm not sure if others are compatible. I can't find one specifically for the 2010 one.
Information:
Mid-2010 21.5" iMac
EMC 2389
About 2.5-3 years old
It doesn't turn on
None of the diagnostic LEDs are lit
Makes a small zzz noise every couple seconds when plugged in
Suspected power supply failure

Switching won't harm your machine.

Power Supply Issues maybe?

I have always had random and instant power downs. Which I initially attributed to heat. The machine is now shutting off instantly several times a day. It starts up and runs fine, but it is shutting down after anywhere from 10 minutes to 2 hours later. I am thinking it is a bad power supply that has gotten worse. I want to bounce this off the experts and see if there is anything else I can eliminate before buying a power supply?
I have reset the SMU I think. I could not find a button so I unplugged for 15 minutes. I ran AHT from cd without errors, ran disk utility from cd, and checked to see if the SMART status is verified. I use temperature monitor which has read as hot as 115, but according to what I am reading that is well below danger.
I did a safe restart to eliminate any font issues since I use a lot of fonts. I don't know what to look for in the console, but I saw nothing that looked suspicious. I am assuming since the AHT found no problems the logic board is functioning properly. Is that correct?
Can you suggest anything else to narrow down my issue?
Thanks for all your help. This machine is within a month of retirement, I think it senses something!

I have had exactly the same problem over the last couple of days and it drives you nuts! It started to happen just after I transferred some files to a mates cheap firewire drive....no idea why...
You can try actually pressing the SMU button
http://docs.info.apple.com/article.html?artnum=300341
These two articles also take you through a good process, including deleting some prefs.
http://www.gibbilicious.com/gibbilicious/2006/02/troubleshootingthemysterious.html
http://www.gibbilicious.com/gibbilicious/2005/10/mac_g5_desktop_spontaneously1.html
Also check all the bits inside are connected. The airport card can get loose in particular. Double check memory is pressed in etc.
I tried it all but to no avail until I read your post and tried Safe Restart. For some reason it dumped a load of files in my trash, but the issue seems to be gone (at least for now). I don't wanna detract from helping Kenny, but whilst peeps are looking if anyone can shed some light on what they are and whether I should bin them it would be good.
All in a folder called 501.231504386 and called annex_aux, annex.db, Classic.fodb, filetoken.db, font.db, Local.fcache. Local.fodb, qdfams.db, System.fcache, User.fodb

Moving to Germany with my IMac- Power Cord issues

Hi,
Does anyone know how I can safely use my iMac G5 in Germany? I bought it in the U.S. but will be moving to Germany for 2 years. I would like to bring my computer with me but as far as I know, the line voltage of my computer cannot exceed the following:
 Line voltage: 100-120V AC
and Germany uses a 220 volt/50 hertz system. How should I deal with this? Can i just use a regular power converter?
Thank you,
heringji
iMac G5 Mac OS X (10.4.9)

G'day Jill,
You can find the instructions for replacing the built in power supply yourself at http://manuals.info.apple.com/en/imacg517inch_PowerSupply.pdf
These people will sell you one for $145 (the ALS PS also fits the "first generation" models), or replace it themselves for you for $195. (about the same price many Apple places charge for the part alone)
Expensive, I know, and you can get a 350 watt (about the size you need to relaibly run an iMac) "voltage converter" for significantly less, but if you go down the latter path make sure you get a good one.
Cheers
Rod

Whining Power supply yet again..........Macbook 2.16GHz New Rev

So i got my new Macbook 2.16Ghz C2D today and expected it's avery lush machine. There is however one problem and i've had this with every mac notebook i've ever owned. The whining from the power supply/Macbook when it's on charge.
It's like a high pitch digital noise which constantly bugs you in the background.
I'll give Applecare a call on monday.

So i got my new Macbook 2.16Ghz C2D today and
expected it's avery lush machine. There is however
one problem and i've had this with every mac notebook
i've ever owned. The whining from the power
supply/Macbook when it's on charge.
It's like a high pitch digital noise which constantly
bugs you in the background.
I'll give Applecare a call on monday.
Seems like this will never be remedied across the board.
My 17" MBP still has the issue in the form of a "hiss".
Maybe its the nature of the beast.
William

MSI GT680 Power Supply Issue = Performance drop

Hello,
I have a MSI GT680.
Recently my computer has developed fps issues with games like minecraft, LoL, dota2, etc. Which were previously very easy to run without any problems.
I believe it is something to do with the power supply, When I hover over the battery icon in the bottom right it says (plugged in, not charging)
and the computer performs the same plugged in as it does unplugged.
Ive tried to fix the (plugged in, not charging) issue but nothing has worked so far.
I just need to know if I have to buy a new charger/battery or if its just a software issue
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Check which power scheme is selected. Power scheme "balanced" will do nicely in most situations and for testing.
Check if the graphics speed (GPU/graphics memory speed) is the same in the plugged and unplugged state when running the game.
You can do this by running MSI's Afterburner software.
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Power Supply Issues Part 2

This is a copy of my last post plus the new item. I recently received a Power Mac G4 server (450) over the Holidays (last year)and plugged it in and made sure very thing work and what not. Took it on the plane home plugged it in when i got here and it worked and hadn't messed with it since I had too make up at work for the vacation I took. A couple of weeks later went to turn it on and the power button lights and the fan turns on for like three to four seconds then shuts down every time. Was unplugged the entire time wasn't in use so its not a surge problem. Do I need a new power supply or is it something else? (Today) I also have a Power Mac G4 (fw800) and shut it down last night and when I went to start it this morning it did the same thing. Nothing was tripped in the surge protector and everything was fine shutting down. This is getting very annoying. Plus I never did replace the power supply on the g4 (server) so I am going to go through the same test from the last time. I need some help, I got two units down now, not that i don't enjoy playing on my iMac 266. what I do know so far is that the battery is not dead. Measured out at 3.58V
iMac 266 Rev. B Mac OS X (10.4.7) Too many to choose from...

And have you replaced the PRAM battery? Just testing is not enough, it needs the voltage under load. Radio Shack, OWC and other vendors sell them.
For PSU prices, see this:
http://www.dvwarehouse.com/categories/253238_247476.html&pltid=3721ba506600734a7fe4958acbbc2d88
For install help, look here:
http://www.apple.com/support/diy/

G5 20" iMac Power Supply Issues Again!

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