iMac G3 will not start up

Question

Level 1

11 points

iMac G3 will not start up

This morning when the power button is pushed, nothing happens at all. The button does not light up. The computer does not start.

I checked the power cable. I took it out of the computer and put it back in. (I did note that the plug looks a bit darkened but it does not smell burnt.) I tried it in a different outlet. Same thing. It won't turn on.

I can't recall if this iMac is a G3 or G4 and I can't find my documentation to let you know. But I don't know that it matters which G it is. It is the old special edition grey iMac and has been working for us for many years.

Is this the end for this iMac? Could it be something that is simple to fix?

Ginny

iMac, Mac OS X (10.2.x)

Posted on Apr 9, 2012 6:36 AM

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Answer 1

Apr 9, 2012 11:07 AM in response to Ginny C.

If it's transluscent grey with a CRT display, it's an iMac G3 (slot-loader).

One thing you can try is to press the PMU reset button. This is the location, and procedure.

http://mrjcd.com/junk/PMU.jpg

As it says, be sure to press it only once. It says to check the PRAM battery. You don't need to do that before trying the PMU reset. However, a dead or weak PRAM battery could be the reason your iMac is having this problem.

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Answer 2

Ginny C. Author

Level 1

11 points

Apr 9, 2012 8:47 PM in response to Kenichi Watanabe

Our model is the Graphite G3 Special Edition iMac. Yes, a slot loader.

Thank you for the link. I'll give it a try. Not tonight but soon. We did buy a new iMac today but I would fix the old G3 if it is possible.

On the page that you linked, it mentioned the possibility of a dead battery (BT1) but I can't figure out in the picture that is shown where the battery is. I don't know what BT1 means. Do you know if replacing the battery is something that can be done easily too? Can the battery be seen in that picture? Do I need any special tools?

In looking through the discussions earlier today, I saw something about SMC and I took out the power cord and the keyboard and mouse and held the power button in for five seconds. Then put the power cord back in and pushed the power button. The button lit up for a very brief fraction of a second. Then it would not light up again.

Thank you for your assistance.

Ginny

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Answer 3

Apr 9, 2012 9:43 PM in response to Ginny C.

I don't know what "BT1" is either. However, the battery is supposed to be reachable through the opening used to install RAM (which is the opening shown in the PMU reset picture). My old iMac G3 was a tray-loader, so I don't have personal experience. The battery looks like this

http://eshop.macsales.com/item/Newer%20Technology/BAA36VPRAM/

I found this web page with helpful information

http://dssw.co.uk/sleepcentre/threads/replacing_battery_in_g3_imac_dv.html

The "SMC" procedure is for newer iMacs (although it would do no harm to try it on your iMac). The equivalent procedure for the iMac G3 is pressing the PMU reset button.

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Answer 4

Jeff

Level 6

12,328 points

Apr 10, 2012 7:15 PM in response to Kenichi Watanabe

Although the battery can be seen on the motherboard through the memory access door, getting a firm grasp on it for removal and installing the new one is no easy task, given the clearance issues. If it slips from your fingertips, it will roll down the motherboard and you'll be tilting the iMac in every direction to shake it out. Additionally, you need to note the polarity orientation of the existing battery, so that you install the new one identically. The non-shortcut method for battery replacement involves placing the iMac upside down on its sloping top and removing the bottom plastic housing. Following that, the EMI shield that covers the motherboard needs to be removed. Although it's more trouble, it provides you with unrestricted access to the battery.

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