iMac G3 (Bondi-blue 233MHz tray loader) screen stays dark after firmware upgrade

[Fabri91]

I've recently had the opportunity to play around a bit with a tray-loading iMac G3 (233 MHz model), and after a quick and painless RAM upgrade I decided to try to install OSX 10.2, where I neglected to perform the firmware upgrade prior to OS install. I'm aware that there are some issues with the later slot-loading models and the screen timing being borked on OSX, but this seems to be a different issue: OSX 10.2 worked fine, with the exception of the system booting to OpenFirmware needing the "mac-boot" command to load the OS.

However, after learning that a firmware upgrade was available I deciced to perform it anyway to prevent any further issues. To do this I re-installed the factory-shipped Mac OS 8.5, which worked perfectly. Afterwards I performed the firmware upgrade and everything seemed to go well, up to and including a progress bar being displayed upon reboot, after which the screen went dark and hasn't been able to turn on.

If I try to boot the machine disk access sounds can be heard, like during a normal boot, with the exception of the monitor staying dark.

Some other possibly important points:

• the firmware upgrade was performed with the Real-time clock battery removed, due to it being flat and waiting on a replacement. Could this cause the firmware corruption?
• the firmware upgrade was performed with the Real-time clock battery removed, due to it being flat and waiting on a replacement. Could this cause the firmware corruption?
• No VGA port available to connect a second monitor

I have a 160GB IDE hard-drive laying around, if it could be useful

From what I've read in these early models the firmware is actually stored in a chip on the detachable CPU card. If that's the case, could a CPU card replacement resolve the issue? If not, could it be helped by replacing the logic board and/or any other components?

Thank you for any help!

 

[harryb2448]

With your iMac the firmware update had to be done prior to commencing the OS X update. At the time, 1995 or so, it was thought proceeding could fry it. Have a read of this uner OS X about the update first:-


http://lowendmac.com/1998/original-imac-rev-a/

 

[pm-r]

I don't know what you might be planning to use that old iMac for these days, but it won't be for too much, at least when connected to the 'net and won't be very constructive unless you're writing a novel or some such.

But to get it running, you might want to try putting the original RAM back in and see if it will at least boot. It sounds like that's when your problems started as well along with the OS upgrade.

 

[Fabri91]

I don't know what you might be planning to use that old iMac for these days, but it won't be for too much, at least when connected to the 'net and won't be very constructive unless you're writing a novel or some such.

But to get it running, you might want to try putting the original RAM back in and see if it will at least boot. It sounds like that's when your problems started as well along with the OS upgrade.

It was just curiosity that prompted me to tinker around with it, not the intent to use it as a "normal" machine.

I'm afraid I already tried to put the original RAM back, even just the 32MB default SO-DIMM, with no change. In fact, the system worked ok with the new RAM for some hours and only started to present a black screen after the automatic reboot following the firmware update. Connecting an older Mac CRT to the display connector also yields no results.

 

[pm-r]

It sounds like yet another iMac Bondi-blue Macquarium maybe coming up sometime soon…

As much as I appreciate some of the older Macs, and some still workable in the basement. LC 630 fully loaded and G3 DT Mac and some Apple displays…

 

[cradom]

Those old iMacs wont boot without a working battery. (ask me how I know )
Put a good motherboard battery into it and see what happens.
However, as was said above, don't expect much out of it when you do get it working.
It's just too old for much more than just messing around with old stuff.

 

[Fabri91]

Putting the battery in or out doesn't change anything (in fact the system was run for some days without the battery and everything worked as it should with the exception of the system date being forgotten when unplugging the system).