I finally got my hands on a Color Classic ! Though there’s a little issue.
When I turn on the switch on the machine after honking everything up, the transformer makes a normal « stand-by » noise, but when I press the power button on the keyboard, the Mac doesn’t start up. I tried with multiple keyboards and cables, none seem to work..
I then tried to remove the logic board to see if the analog board powers up, and *it does* (the fan spins up, the hard drive starts, the flyback transformer makes its classic noise)…
The next thing I tried is, from stand-by, removing and directly plugging back in the motherboard. And finally, the beasts boots up ! It gets to a desktop, runs programs, lives.
So what about the power button ? Well, when the machine is running and I press the button, the system asks if I want to turn of the machine; so it is in fact working, and on all the keyboards I tested this.
So my issue is : The Color Classic doesn’t boot whet I press the power button on the keyboard, but when I get it to boot the button is detected.
Does anyone know what could be the cause of this issue, and what could possibly fix this ?
I’m already planning on recapping the motherboard and analog board, and I didn’t have the time yet but I’m going to clean the all the contacts of the connectors (though I don’t think the issue comes from here as the machine works correctly when it has started).
Check the battery?
Yes, this is a PRAM battery issue -- a common thing in Macs from that vintage. They won't boot if the battery is dead. As you found, there's various ways to "jumpstart" them (for machines without soft power, another trick is to rapidly flip the power switch on, then off, then on again), but the 1/2AA-sized batteries are still available and relatively inexpensive.