(Another) iMac G3 black screen issue

Question

All right, I'm sure questions about the CRT going black are pretty common, but I've scoured the net for fixes and am still coming up blank. Here's the problem...
Just bought a used iMac G3, slot loader. I think it's one of the early ones, as there's no VGA port in the back under the pop-off plate to use a second monitor. The guy I bought it from knew nothing about its history other than "the screen doesn't work".
Took it home, turned it on. The power light goes on, the hard drive spins, the screen makes those CRT sounds like it's going to come on, but it's completely black. So, I hit the forums and have tried the following solutions:
1. Reset the PRAM.
2. Replaced the PRAM battery with a new one.
3. Remove the memory, then battery, then pressed the PMU button (once), waited, replaced the battery, then memory.
4. Inserted an OS 9 CD, held down C during startup. Heard it spin around, didn't do much else.
5. Gone into Firmware mode, reset the NVRAM.
6. Let it boot up, waited till the hard drive stopped spinning, pressed the power button to try to put it to sleep. Nothing happened.
7. Held the button on the side down while restarting. That may have been a bad idea, I dunno, but I was running out of things to do and figured it's probably already fried anyway. It beeped in acknowledgement, but no other changes.
Any other ideas? I've hit all the places I can think of. I don't care much about saving anything on the HD -- I have no idea what's on it anyway -- but I'd like to get this running as it's intended to be used for a non-profit. As always, I'd like to make spending cash on a replacement part a final option; it seems people jump to that conclusion prematurely pretty often but it may be about that time...
Last thing. If this thing is definitely dead, are there any parts inside worth salvaging? Maybe I can gut it and have a nice Macquarium. Any links to a good page on how to safely discharge the CRT and take this baby apart?
Thanks in advance for any tips.
iMac G3 (slot, 350?)    

Answer 1

Hello and Welcome to Apple Discussions,
I actually successfully took one of these iMac G3's completely apart and replaced the entire CRT component, leaving all other parts inside. The CRT in my machine did work before I replaced it, but it had a " dark shadow" which grew worse as time went on (making it hard to see), so I decided to replace it with a newer one. What I recommend you do is try one last thing because you just bought it. There are "hidden" CRT controls for the brightness and contrast inside of the bottom case (two plastic knobs). From what I am reading, it sounds like the entire CRT is bad and will not power on/function properly, but you can try to adjust the brightness/contrast anyway just to be sure. The fact that you hear the CRT sounds makes me think it is possible the brightness/contrast are all the way down, which would be why you only see a black screen when powered up. To locate these knobs follow the instructions below:
1) After completely unplugged, place your iMac G3 upside down on a soft surface (such as a bed).
2) Using a screwdriver, remove the two screws located near the front end of the machine.
3) After removed, pull upward and remove the plastic housing.
4) Look for two black knobs on the sides of the machine and plug in the power cord.
5) After you hear the chime, turn the knobs back and forth to try to get a picture.
6) If you do not see a picture, your CRT or (parts that connect to it) are probably broken.
7) Remove the power cord.
8) Replace the bottom plastic housing and screw it back together.
I hope this helps you solve this issue you are having. If it does not work out, I will think of something else. Also, do you hear the start up chime and does the power light always remain lit green the entire time the machine is powered on?
Jason