You could perhaps try running Snooper when you successfully boot into System 6. It goes through a series of hardware tests, so it might give some clues as to the cause. For example, I had a Mac Classic that would boot into System 6, but stopped while loading System 7. It turned out that System 7...
I used a CY8CKIT-059 prototyping kit. It comes with a programmer and is super cheap.
I'm actually in the process of making a YouTube video of the whole build.
I know this thread is a couple of years old, but I'm going down the path of building the v4.2 SCSI2SD for the mountain of beige Macs I have, and I'd appreciate any assistance. I can't seem to get the SCSI2SD to play nice. I can get the bootloader on there, I can load the firmware with the...
So when you run HD SC Setup, does it recognise the SCSI2SD drive at all? What happens when you try and format it? Have you tried any other formatting utilities such as Hard Disk Toolkit, Silverlining or Lido?
Slight update to my post. That original link is incorrect, and this is the correct item:
https://au.rs-online.com/web/p/ir-leds/1713858/
Although functionally the same, the other ones are slightly the wrong size and required a bit of fiddling to get them in. The link in this post is the...
Although I appreciate that the capacitors are probably not the cause in this instance, please get it recapped ASAP. The Color Classic is one of the worst for getting damaged by capacitor leakage.