eMac A1002 won't boot up

Hi,

You should probably immediately stop trying to use the computer. Otherwise, you run the risk of erasing or overwriting files (this may have happened already). Depending on the importance of the files on the hard drive, you would have to decide what to do next.

You may want to have the hard drive removed from the computer. Warning: Opening an eMac is dangerous, and must be performed by qualified personnel only. There are high-voltage circuits inside. Dangerous charges can remain in various components even with the computer turned off and disconnected from the mains. Do not open the computer yourself!

If the files are very important, you should ask a company specialised in data recovery for assistance.

If the files are not that important, you could connect a removed hard drive to a USB universal bare drive adapter (similar to the example at https://eshop.macsales.com/item/NewerTech/U3NV2SPATA/) and use another appropriate Mac (or PC, with special software) to try to to read the contents of the hard disk.

Without having had the hard drive removed from the eMac, and if you are willing to risk (further) data loss, you may even want to experiment with the eMac in FireWire target disk mode instead (see page 27 in the manual). Access to another FireWire Mac would be required. If the basic functions are OK, there is a chance that the eMac then would appear as an external drive on the desktop of the other Mac.

The condition of the logic board battery (page 44 in the manual) may or may not have something to do with the startup difficulties.

https://manuals.info.apple.com/MANUALS/0/MA475/en_US/eMac_Early2004UserGuide.pdf

Welcome!

Although there are four eMac families, every eMac ever made is a Model A1002. Some variants, especially those marked as 2004 models, have fatal logic board issues that make any further work on your part akin to beating a dead horse.

The Apple articles about how to tell anything about an eMac model are now gone, but I saved some of that info:

"020-3991-A. " is not a serial number. Manually open the optical drive door (I use a fingernail when the computer won't start) to find your "real" serial number:

⚠️ Do not post the serial number here.

Use this chart to find your model from the last three characters of the serial number:

If your eMac's serial number puts in it the "USB 2.0" group, look at the first FIVE characters and see if they fall in these ranges.

If so, the computer will not work without a new logic board. Those are unavailable because so many went in to fixing the massive number of failed USB 2.0 2004 eMacs through a Repair Extension Program that is long expired. Any boards offered "used/pulled" is likely to have the same issue.

The 2005 models are unaffected and are rock-solid performers were is not for being constrained to no higher macOS version than 10.5 Leopard.