Power Mac G5 won't boot & loud fans

Thanks for the suggestion, will look into getting the right battery locally since shipping cost + time doesn't make sense.

In answer to your question, it does take longer for the fans to ramp up if cooled down completely. But I get no further in the boot process.

It does not boot at all from the install disk -- I think I misspoke when I wrote that the install disk loaded prompted the hard drive to load -- that was just a fluke. I've tried 3 times now to boot the machine with disk loaded, and only get the grey Mac screen. Holding C down during the boot process has no effect.

I also just tried a boot with the install disk loaded (holding down C), with no hard drive installed (removed the hard drive). Identical results: grey mac screen loads and hangs there, then fans start to go into turbo mode again. No boot from the drive at all.

BDAqua wrote:

will look into getting the right battery locally since shipping cost + time doesn't make sense.

Yeah, just posted that so you could see what you're looking for mainly.

I really appreciate it -- very helpful.

Does it boot into any of these modes? (and other helpful suggestions)

(will check the rest in a few minutes and get back to you)

Thanks again

Message was edited by: deadbeats

OK this is what happened:
1. Connected my keyboard and mouse directly to the USB ports on the computer in case the computer was having an issue with the connection via the display.
2. Started the computer in Target mode. Displayed Firewire screensaver, but that's it -- I don't have another computer to connect via firewire, so I figured that's OK. I was glad because this meant the computer was still responding to keyboard commands (was afraid it wasn't any more).
3. Rebooted the computer, this time in Single User mode. Computer hung at one of the prompts, and fans kicked into turbo.
4. Hard booted computer, tried Single User mode again. This time I got all the way to the # prompt. Typed in /sbin/fsck -fy and used this page [http://support.apple.com/kb/TS1417] extensively. Was returned the message, "The volume Mac OS X install disk 1 appears to be OK". Rebooted, ran /sbin/fsck -fy again, just in case. Same result. I got a bit worried because I wasn't sure why it wasn't seeing the hard drive. Recalling some distant unix commands, I tried /ls to see what happened, but couldn't remember much more than that.
5. Rebooted again, this time with C. This time the installer worked, and I ran disk utility. Clicked on "repair disk" for the hard drive, which found file structure errors. Rebooted again in safe mode. Panic kernel errors. Ack.
6. Rebooted from install disk again, ran disk utility again. No errors found. Repeated again, just in case. Skipped trying to reboot in safe mode.
7. Took out the install disk, and tried to start the computer normally. By the way, up until this point, all fans were NORMAL. NO TURBO AT ALL.
8. Computer started up beautifully. Ran disk utility to verify the drive, then to verify file permissions -- no errors.
9. Rebooted computer again, normally. Ran a few software programs and checked the hard drive structure to see what was there. No problems.
10. Powered off. Reconnected essential peripherals. Rebooted. No problems.

Looks like the issue is resolved. Hubby was making a run anyway to get a new battery, which should be arriving in a few hours. Hopefully this is the end of this issue!

Finally, THANK YOU again for all of your helpful advice and troubleshooting. I've never done troubleshooting on a MAC before, this was actually a fun learning experience.

Now to install our shiny brand new 1TB hard drive, and back up that data. After the battery's installed, of course.

Ugh. Now it's worse than ever.

After installing the new battery, I tried to reconnect one of the external SATA hard drives (LaCie) that used to be connected to the computer via firewire, and it now won't boot at all. Same error as before: hangs on grey mac screen. The only difference is that there is no turbo fan sound now.

The machine won't boot from the install disk, and won't start up in single-user mode. It did start up in target mode, but since I don't have another firewire computer to connect to, this doesn't really help me much. Doesn't matter that I've long disconnected the external drive; it now won't boot.

I flushed the NVRAM using this page [http://support.apple.com/kb/TA23401], but nothing changed -- still got the grey screen when I tried to reboot from a disk.

Any ideas?

Computer won't boot again

Latest update:

Disconnected all peripherals, let the computer sit overnight (still AC connected), and tried a boot from disk this morning. No dice.

Tried again in single-user mode, success: got to run /sbin/fsck -fy.

No errors on the hard drive found, but the fans started to turbo up during the check process.

Once /sbin/fsck -fy was completed, the fans were in full turbo, then I saw the message repeated:

"Going to sleep. Power management emergency overtemp signal"

What now? All fans etc have been dusted. Looks like it might be a heat issue -- if so, what do I do about that?

Decided to reset PMU as well as per your instructions. Restarted in Single-User mode after waiting to reconnect everything, and the screen stalled at "Dart enabled" (next command after this is a Firewire check).

Did a hard boot, tried again to restart in single-user mode. This time got to the hash prompt, and ran /sbin/fsck -fy. No disk errors, but as the check was in its last step ("**Checking Catalog hierarchy") the fans revved up and started to go into Turbo again. I didn't wait for the system overheat emergency error, and typed "reboot". Fans immediately died.

System reboots in single-user mode again. Fans quiet the whole way, we get to the hash prompt, and I run /sbin/fsck -fy again. Again, when we reach the last part "**Checking Catalog hierarchy" the fans start to rev again. fsck completes, no disk errors again, and the fans are in full blast.

I shut down the machine.

The battery has the correct polarity, btw, but I am going to try putting in the old battery just in case, since that was the last time there was some success.

Will update you on what happens.

Amazing. Your insistence on checking the battery led me to this post [http://timesync.gmu.edu/wordpress/?p=447]. The comment by "Nealer" on October 25th, 2009 tipped me off: turn the battery in its cradle.

I did, a few times. Turned on the machine with its old battery installed, booting up from the install disk. Ran Disk Utility. No disk errors. Rebooted, fingers crossed, normally. Ran like a charm.

Turned off the machine, took out the old battery, put in the new one. Turned it in its cradle a few times backwards, a few times forward, for luck. Hubby and I both crossed our fingers.

Turned it on. Ran like a charm. Shut it down through the Mac OS; plugged in the monitor's firewire. Turned it back on. Nothing but peace and love and good times.

Powered down again. Plugged in an external hard drive on a firewire port. Turned it back on. Sweetness and light. Ran disk utility to check the external drive. No problems. Ran disk utility on the local drive because I am struggling with the "too good to be true" feeling.

And repeated until all peripherals were connected. No issues, whatsoever. I swear the computer was smiling at me.

So I played Bob Marley's "Coming in from the cold" and it's cycling through iTunes now as I type this note with a smile on my face. Never thought that song could sound so sweet.

Thanks again for all your help. Really appreciate it. Will let you know IF there are any other problems. Next up is installing our new drive, but I'll do that after a week of stable runtime.

I hate to say it, but... the problem's back again 😟

It seems intermittent. I really don't know what the problem is. I think it might be time to say adieu to the unit.

Unless it doesn't require substantial commitment of time and energy, I just don't think it's worth it to keep pouring effort into a no-longer supported model, in any case. We'd already been experiencing software incompatibility issues. Might be time for a new machine. :-\

Still open to suggestions, of course. The remaining two possibilities are faulty logic board and failing thermal paste. How much is a new logic board? (Worst-case scenario).

Sorry... totally bummed.

Problem remains. 😟