It was the analog board! I still need to test a bunch of things, but I recapped the analog board and reflowed all the solder on the various 12v power connectors, and now I'm getting this:
Thanks for the help, all! I was sure I was SOL for a while there.
Thanks. Reassembled and checked at the floppy connector. 5v seems fine (several pins read 4.9v, one reads 4.6v) but the pins I think should be 12v based on this pinout guide are reading 2.8v. Strangely, the -12v pin seems OK at -11.7v.
At PSU (no load)
At Floppy Connector
5v
5.3v
4.9v...
Hi all! First post here, hoping for some advanced help. Thanks in advance!
I picked up a Mac SE that I'm trying to get working again. It was initially booting to a checkerboard screen:
My first stop was to clean the motherboard (which didn't look too bad) with alcohol, and re-seat the ROMs...