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View Full Version : iMac G5 capacitor help/information




iLucas
Apr 13, 2011, 10:53 PM
Hello all, I have recently received a iMac G5 for very cheap, I tested the machine and i have no display. The first 2 LEDS come on and the third does not. i believe the issue with it is blown capacitors, although im not 100% on this. I have never dealt with a capacitor issue so i'd figure i'd ask if that really is the problem, so it can be fixed. Heres an image of my iMac
http://img687.imageshack.us/img687/3891/photo3mr.jpg
Are the ones on the left needing replaced? Theres about 15 in the machine that look similiar, and few that look like whats on the right.
If this is indeed my problem, where could i get the capacitors that i need?



sjinsjca
Apr 13, 2011, 10:57 PM
I'm not seeing anything unusual with those caps, but could you describe what you see a little more? What makes you suspect those caps?

iLucas
Apr 13, 2011, 11:03 PM
I'm not seeing anything unusual with those caps, but could you describe what you see a little more? What makes you suspect those caps?

The ones on the left look really fat to me. As i said i could be wrong on this, i don't know much about capacitors. But if the things on the left and on the right are both capactiors, then the ones on the left are 2x the size of the ones on the right in person. They are also taller. is this normal?

I saw this image on google and read several other posts on forums and they said the 3rd LED could be a capacitor issue.

http://www.pcstats.com/articleimages/200302/capblown_3.jpg

Hrududu
Apr 14, 2011, 12:10 PM
Yours look fine. I've replaced caps on about 12 iMac G5 systems and they are usually VERY obvious when they go bad. By that I mean electrolyte spewing out of the tops. Out of those 12, 9 of them worked again after replacing the caps, so if that does happen your odds are pretty good that it can be fixed.

iLucas
Apr 14, 2011, 12:28 PM
Yours look fine.

Well that's good to know,
But now i'm not sure what other problem my iMac could have.
Any one have any clues?

ChrisA
Apr 14, 2011, 01:20 PM
Hello all, I have recently received a iMac G5 for very cheap, I tested the machine and i have no display. The first 2 LEDS come on and the third does not. i believe the issue with it is blown capacitors, although im not 100% on this. I have never dealt with a capacitor issue so i'd figure i'd ask if that really is the problem, so it can be fixed. Heres an image of my iMac
http://img687.imageshack.us/img687/3891/photo3mr.jpg
Are the ones on the left needing replaced? Theres about 15 in the machine that look similiar, and few that look like whats on the right.
If this is indeed my problem, where could i get the capacitors that i need?


Do you see those lines across the top of the capacitors. Those are there so if the device fails it will be a more or less controlled explosion where the metal slips on those lines. Failed caps are dead on obvious and make a big mess

If yu really do think one is bad un-solder it and test it. It takes all of 5 minutes and you've got not much to loose

There is absolutely no way to diagnose this without some test equipment. Get at least a multi-meter and likely a meter and an oscilloscope. Then

If you do need to replace them they are 25 cent parts and you don't nee a perfect exact match any electronic parts place will have them.

There is no way to look at this without some test equipment, you cannot see the signal in the traces with your eyes not can you visually see a defective component except in the extreme case of one that has let out some fire and smoke

iLucas
Apr 25, 2011, 11:20 PM
Some new news on the iMac. I got a mini vga to vga adapter today to plug into an external monitor and i get nothing. Nothing on the iMac display and nothing on external display when turned on. What does this mean?

Hrududu
Apr 25, 2011, 11:46 PM
Just to clarify, it does chime and the light on the front does fade to off after its turned on right? If its doing all that, its most likely a bad graphics chip.

iLucas
Apr 26, 2011, 12:16 AM
Yes that is correct. It does chime, and the light flashes. After about 5 minutes the fan start to speed up and that's all it does. I never see anything on either screen.