iMac No Longer Powers On

[zackkmac]

Hi all. I just purchased a C2D 20" iMac that had a busted LCD. When it arrived, everything worked fine, but the screen was unusable. So I powered it off, unplugged it and left it in my closet for nearly two weeks.

Last night, I removed the broken LCD and installed a new one, and while I was in there, I cleaned the fan and changed the HDD to an SSD. I wanted to test it before putting it back together completely, and sure enough, it does not power on. It now shows absolutely no sign of receiving power. I located the LEDs on the logic board and they don't even illuminate. One thing I should note is that I did *not* check it for power again before disassembly as I assumed it was still working fine. So I am not sure if it "died" before or after replacing the LCD.

Any tips/suggestions?

[justperry]

How did you clean it, you have to be careful, Static electricity can easily damage a logic board and/or the power supply.

[zackkmac]

I used a can of computer duster and blew out all the thick black lint-type fuzz in the fans. It was the grossest fan I'd ever seen to be honest. The small round vent on the back of the iMac (around the power cord area) is also completely black with this stuff.

[BeeJee]

Sounds like a smokers home.

[zackkmac]

It most definitely came from smokers, it reeks of it. Poor thing. I really do not want to shell out $40+ for a new PSU though...

[justperry]

Originally Posted by BeeJee

Sounds like a smokers home.

Completely irrelevant.

Originally Posted by zackkmac

It most definitely came from smokers, it reeks of it. Poor thing. I really do not want to shell out $40+ for a new PSU though...

What I said before still stands but normally if you take care it won't be a problem, since most Macs are aluminium you can touch the metal before anything else to discharge, it also depends on the person which does it and the kind of weather and tools.
If you are not a person which is "charged", in a bit humid weather and don't use air form a compressor together with non generating tools you're OK.
I openen plenty computers without the special discharging arm wrist and did not have any issues.
But, as an Electrical Engineer I also saw boards damaged by static electricity, just 2 years ago we got 10-15 of them damaged by a single person (Charged), (Hi tech boards for Toll road signalling),

[zackkmac]

Thank you for that info justperry. I guess it was somehow damaged by static electricity. On a side note, it is a white C2D iMac but I used the metal frame on the bottom to discharge.

I just plugged it in to see if maybe it would revive and the PSU sparked big time. It actually was one large bright spark accompanied by a large POP. Now the room smells of smoke and the PSU has turned brown in some spots.

I really, really hope this didn't zap the logic board.

[BeeJee]

Originally Posted by justperry

Completely irrelevant.



What I said before still stands but normally if you take care it won't be a problem, since most Macs are aluminium you can touch the metal before anything else to discharge, it also depends on the person which does it and the kind of weather and tools.
If you are not a person which is "charged", in a bit humid weather and don't use air form a compressor together with non generating tools you're OK.
I openen plenty computers without the special discharging arm wrist and did not have any issues.
But, as an Electrical Engineer I also saw boards damaged by static electricity, just 2 years ago we got 10-15 of them damaged by a single person (Charged), (Hi tech boards for Toll road signalling),

Who put you in charge to decide what is and what isn't relevant? OP even acknowledged I was correct. Smoking is known to be bad for electronics and I was making a statement on why there was probably black looking lint.

[justperry]

Originally Posted by zackkmac

Thank you for that info justperry. I guess it was somehow damaged by static electricity. On a side note, it is a white C2D iMac but I used the metal frame on the bottom to discharge.

I just plugged it in to see if maybe it would revive and the PSU sparked big time. It actually was one large bright spark accompanied by a large POP. Now the room smells of smoke and the PSU has turned brown in some spots.

I really, really hope this didn't zap the logic board.

If you touched the metal it normally will equalise the voltage, so this might not be the problem here, you might have moved something and it short circuited.
Hard to tell, the photo is with flash, can't see much there.

Originally Posted by BeeJee

Who put you in charge to decide what is and what isn't relevant? OP even acknowledged I was correct. Smoking is known to be bad for electronics and I was making a statement on why there was probably black looking lint.

If this was/is the case many more electronics in smokers houses would be affected and this is just not the case.
Electronics always attract dust (especially when high voltages are present), smoking or not.

Edit: But, you are partially right, if people smoke it gets greasy and dust will stick to it, so yeah, I said things to fast, it is relevant, sorry about that.

[zackkmac]

Sorry about the photo; the non-flash version did not show well either. The top-middle portion of the PSU (as well as the tape strip above it) turned a bit brown.

I guess I messed it up but I thought I took all the right precautions. I've repaired the same exact computer before (and many others) so I did not see that coming.

Anywho I've just sold it on eBay for much more than what I paid for it and the screen so I'll let the new buyer diagnose its problem or use it for parts. I could've bought a new PSU and if it had worked then still made some profit, but if it had fried the logic board too (which is very likely) I would've been at a loss. Not worth that risk.

Thanks for the input to the both of you.

[justperry]

Originally Posted by zackkmac

Sorry about the photo; the non-flash version did not show well either. The top-middle portion of the PSU (as well as the tape strip above it) turned a bit brown.

I guess I messed it up but I thought I took all the right precautions. I've repaired the same exact computer before (and many others) so I did not see that coming.

Anywho I've just sold it on eBay for much more than what I paid for it and the screen so I'll let the new buyer diagnose its problem or use it for parts. I could've bought a new PSU and if it had worked then still made some profit, but if it had fried the logic board too (which is very likely) I would've been at a loss. Not worth that risk.

Thanks for the input to the both of you.

It still amazes me people pay so much for dead gear, a couple of weeks ago someone bought an empty iMac box for more than $250.

[manual123]

whats the model year? or better yet the model number?

oops i didnt see that previous post

[justperry]

Originally Posted by manual123

whats the model year? or better yet the model number?

oops i didnt see that previous post

Can't write either.

Just kidding.

[manual123]

Originally Posted by justperry

Can't write either.

Just kidding.

Lol truth!

[zackkmac]

Originally Posted by justperry

It still amazes me people pay so much for dead gear, a couple of weeks ago someone bought an empty iMac box for more than $250.

Yeah people take advantage of others' lack to read the description fully. I remember when the iPhone 5 came out people were selling the boxes for over $1000. But as far as eBay goes I know they have a team that scouts for that and cancel those kinds of listings.

Now my iMac G4 won't power on.

Edit: Just tried the G4 in the kitchen and it powers on just fine. So now I have concluded that the iMac C2D was in fact working fine, rather, my outlets are having issues on this wall. When I tested the C2D one last time on this wall, it blew a breaker/fuse and consequently fried the PSU. Should've done tried another room and it would've lived. Damn.

[justperry]

Originally Posted by zackkmac

Yeah people take advantage of others' lack to read the description fully. I remember when the iPhone 5 came out people were selling the boxes for over $1000. But as far as eBay goes I know they have a team that scouts for that and cancel those kinds of listings.

Now my iMac G4 won't power on.

Edit: Just tried the G4 in the kitchen and it powers on just fine. So now I have concluded that the iMac C2D was in fact working fine, rather, my outlets are having issues on this wall. When I tested the C2D one last time on this wall, it blew a breaker/fuse and consequently fried the PSU. Should've done tried another room and it would've lived. Damn.

I am into Electrics and electronics, a wall outlet fried the PSU?
That's the first time I heard this, I think the wiring is faulty, how old is the wall outlet, do you happen to have 2 or 3 phase power in the house, if this is true there might be more voltage on the outlet than there should be.

Now, I am not American but in Europe it's 240 Volt in between Live and common wires but 400 volts in between 2 phases, that's a lot more and will kill any electronics in fractions of seconds.

Crap this happened to you, you had a perfectly working C2d before, it's kinda odd this happened now when you cleaned it out.

[zackkmac]

Not exactly sure about what phase wiring I have. But yes it is crap that this happened. No idea how but somehow it appears to me that this iMac is drawing too much power. May have been a dumb idea but for curiosity purposes I plugged the C2D back into the wall just now and it threw the breaker again. Odd to say the least because the PSU is fried so how is this thing drawing enough power to flip the breaker?

Could it happen to be the power cord? I don't see how else this iMac is doing this.