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128keaton

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Jan 13, 2013
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I found a listing on my craigslist for an "apple Imac g5 all-in-one" that needed a new screen. It supposedly chimes: http://memphis.craigslist.org/sys/5175934325.html.

The listing also says its requires a second restart to get it working. Sounds like bad caps. Good thing I enjoy soldering :D. My favorite (albeit 'miss speld' guide is here: http://www.instructables.com/id/Imac-G5-DIY-capacitors-repair/step7/Soldering-and-replacing/) A new screen is $30 (if it turns out to be a screen not the GFX card, which I have a heat gun for).

What else?
 
Keep in mind that due to the lead free solder that Apple used you are going to need a very powerful desoldering iron.
I have a very nice Weller. I can't remember the wattage, but I remember purchasing it because my old one struggled getting hot enough. If push comes to shove, I have a buddy with a professional Hakko setup.
 
I have a very nice Weller. I can't remember the wattage, but I remember purchasing it because my old one struggled getting hot enough. If push comes to shove, I have a buddy with a professional Hakko setup.

I remember that the soldering iron that went to about 650 F would barely even begin to melt the solder. I did more damage burning the board than desoldering the capacitors.
 
I remember that the soldering iron that went to about 650 F would barely even begin to melt the solder. I did more damage burning the board than desoldering the capacitors.
I'll double-check the wattage, but 60W seems to be a good one to use. This one from RadioShack will do the job: http://www.radioshack.com/radioshack-60w-soldering-iron/6400216.html.
EDIT: Mine is a 50/60W, http://www.weller-toolsus.com/soldering/systems/weller-wes51-station-50-60w-120v-wes51.html

850*F. Wow!
 
Update on the iMac. I got it. Its...interesting. It appears to have survived a fire. Inside has soot on the white plastic, the fans have black debris, but it doesn't smell like tar/nicotine. Plus the LCD had water damage. The top metal of the iMac had some rust. It doesn't appear to have hit the logic board, as there is no scorch marks or corrosion. Anyway, I washed the case and fans and I am waiting for capacitors to arrive from Amazon (tomorrow). Only two out of the three diag leds come on, meaning that it cannot communicate with the display. Its either the display, the cable, or the graphics card/logic board. I have a 17" powerbook display with the same connector, but it doesn't work, either because of the bad caps, cable, or graphics card. Will keep you guys updated, but I am also looking for troubleshooting ideas.
 
I would be careful about sinking more than $30 or so into an iMac that has rust forming and fire damage.
Yes, I agree, but it bongs on and the logic board was clean as a whistle.
IMG_3460.jpg


However, a new screen is $30. And the caps are needed for another project, so that doesn't count.
 
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Ok, the caps still haven't arrived. I removed the caps from the board. I also found water marks on the board, one leg of small chip on the board was corrosively blackened, and a pin on the LVDS cable was blackened. I scrubbed the whitish area with a toothbrush and alcohol. The only other place that had corrosion was around the CMOS battery, but its clean now as far as I can tell. Any other things I should do?

Thankfully, if the motherboard is shot, I think its worth it to buy a new one, just because I love this form factor.
 
Ok, the caps still haven't arrived. I removed the caps from the board. I also found water marks on the board, one leg of small chip on the board was corrosively blackened, and a pin on the LVDS cable was blackened. I scrubbed the whitish area with a toothbrush and alcohol. The only other place that had corrosion was around the CMOS battery, but its clean now as far as I can tell. Any other things I should do?

Thankfully, if the motherboard is shot, I think its worth it to buy a new one, just because I love this form factor.

The third LED not coming on and not communicating with the display is one of the symptoms of bad caps. One of the iMac G5s that I repaired did the same thing: bong, first 2 LEDs on and then no display and no 3rd LED. You should be fine replacing the caps :)
I don't wanna know what that iMac had survived... :S
 
The third LED not coming on and not communicating with the display is one of the symptoms of bad caps. One of the iMac G5s that I repaired did the same thing: bong, first 2 LEDs on and then no display and no 3rd LED. You should be fine replacing the caps :)
I don't wanna know what that iMac had survived... :S
Great! Well, my plan for the caps will hopefully work out. I snapped the bad ones off at the base, gonna heat from the other side and push the new cap in.
 
Great! Well, my plan for the caps will hopefully work out. I snapped the bad ones off at the base, gonna heat from the other side and push the new cap in.

A little tip to make it easier: put a little bit of new tin on the old one and heat up the contacts keeping the soldering iron on the new tin for about 30-40sec, then take it off and put it back on again. It will melt a lot easier (the first time I repaired an iMac G5 I had to re-drill the holes because I couldn't get the caps off. 4 iMacs later, I know how to do it :D)
 
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A little tip to make it easier: put a little bit of new tin on the old one and heat up the contacts keeping the soldering iron on the new tin for about 30-40sec, then take it off and put it back on again. It will melt a lot easier (the first time I repaired an iMac G5 I had to re-drill the holes because I couldn't get the caps off. 4 iMacs later, I know how to do it :D)
Ok, cool, thanks for the tip.
 
Ok, I couldnt get the solder to co-operate, so I redrilled the holes. I think my PSU is gone now, or something because I cannot get it to turn on. LED1 is lit, but no matter what I do, LED2 will not light. Its just the logic board, a fan, PSU, and RAM. Either that or my holes. My solder joints are sloppy but wont move, meaning its latched on to something.
 
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