Is PowerMac G4 PRAM Battery needed?

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Level 1

12 points

Is PowerMac G4 PRAM Battery needed?

So my old powermac G4 tower unit is not fully booting up... It goes to grey screen with apple icon and stays there forever. Prior to that it wouldn't even show a grey screen or apple icon.

I found some tips online and one was to hit the CUDO button inside and also to pull the PRAM battery. I did both and now at least the grey screen with apple logo shows but nothing else is working to get to my desktop.

Do I need that battery installed to fully boot up? Is it really necessary? If so can I get a new one anywhere batteries are sold?

Any other tips for getting this old mac to boot? I cant install start up disc cuz I dont know how to get the disc drive to pop open without the drive booting up.

Thanks for any advice here!

Brian

Posted on Jun 27, 2017 11:52 AM

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Answer 1

Jan Hedlund

Level 7

24,403 points

Jun 27, 2017 2:26 PM in response to concort5435

A bad battery may or may not cause startup or video problems. See, just as an example (without knowing your exact Power Mac G4 model), page 85 in the manual at https://manuals.info.apple.com/MANUALS/0/MA666/en_US/0342088-EN.pdf. If you cannot find the 3.6 V lithium ½AA battery locally, try online.

Page 55 in the above manual (regarding the optical drive) could perhaps also be of some interest.

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Answer 2

Jeff

Level 6

12,352 points

Jun 27, 2017 2:50 PM in response to concort5435

If the battery hasn't been replaced recently and the computer has been disconnected from an electrical outlet for an extended period, you should replace it. It's a 3.6-v, ½AA lithium, which is usually carried by battery specialty retailers and some hardware stores, but not the big box home centers. It's also used in alarm system components, so that's why battery retailers carry it. You can also buy from online retailers including this one, which carries my preference (Saft), as shown here.

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Answer 3

Allan Jones

Level 10

80,600 points

Jun 28, 2017 8:27 AM in response to concort5435

I cant install start up disc cuz I dont know how to get the disc drive to pop open without the drive booting up.

Try pressing the Mouse button while you press the computer's power button. That is an old shortcut to open the drive. As it it a keyboard startup shortcut, it should open the drive bay before the failure to boot symptoms appear. It may, however, require an Apple keyboard to work. Not all non-Apple key boards recognize every Apple keyboard startup shortcut.

I found some tips online and one was to hit the CUDO button

It's the PMU reset button and. with your model, "hitting"" it is different than for earlier PowerMacs that had CUDA buttons. Some "helpful" websites fail to point out this critical difference. I hope some misdirected online Tip did not make a mess of your G4.

For your model you press the PMU button once for about a second, then release. DO NOT HOLD IT LONGER! With Beige G3 PowerMacs and earlier you pressed and held the CUDA for about 20 seconds. Do that to a newer PowerMac like your G4 and it can cause problems for which recovery is difficult.

One short push--that's all.

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Answer 4

concort5435 Author

Level 1

12 points

Jun 28, 2017 2:04 PM in response to Allan Jones

Yes I did just a short push... thanks for this info!

I was able to finally get the disc drive open by learning that the mouse click opens it when rebooting. Using Alsoft Diskwarrior now to rebuild directories and attempt to clean and repair things... SIGH its taken 6 hours so far and doesnt look close to finishing.... There's a note that is showing on diskwarrior that processing speed is slow due to disk

Anyway, fingers crossed that this gets me back into the system 10 side of this drive... That is where i have all sorts of files that I need. It seems to boot up to the system 9 version side but it doesn't show my files on desktop... Is there still a way to access all my files from software that is used when Im running OS10 on it?

Thanks

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Answer 5

concort5435 Author

Level 1

12 points

Jun 29, 2017 7:37 AM in response to Allan Jones

So how do I tether my laptop to this old PowerMac G4 to copy files off even though I can't physically boot this thing up to the desktop? I know the apple store did that one time for me on a newer mac where the harddrive was fried and was able to still retreive data.

I can boot using DiskWarrior disc and sometimes it will boot to the version 9OS but not OS10 (this is a dual drive PowerMac G4).

So I am hoping there is a way to tether my laptop to search folders on the bad G4 to retrieve data. Any ideas?

Thanks
Brian

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Answer 6

concort5435 Author

Level 1

12 points

Jun 28, 2017 5:22 AM in response to Jan Hedlund

Thanks for the replies! I will try the battery... Hope that's all it is!

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