Using an Apple II Europlus connected to a Sanyo monitor.
The Apple when turned on lights its power light, and produces a solid "almost full screen block" on the screen.
Is this a common fault?
Any ideas?
As a rule of thumb, I would start checking the voltages from the power supply. If they're OK, check CPU, RAM, ROM and then the glue logic interfacing them, and also the logic devoted to generating video.
Normally, the II Europlus is completely socketed so it's just a matter of patience.
The CPU is a normal 6502, you probably already have one in another machine (e.g. VIC-20, Commodore 1541, PET...) that you can swap.
RAMs are standard 4116, found in 30XX PET, the first 16K of a Spectrum and many other computers. If I'm not wrong, the II+ doesn't need all of the 48K to boot. You may try swapping the first and last row of chips, for example.
The logic ICs are all standard 7400 parts (with the possible exception of 8T28 and DP8304N), several coming in more than one piece aboard so you can try swapping them and watch out for changes.
The real problem might be the ROMs... in the event of faulty ROM(s) you'll have to burn a 2716 replacement and build a small adaptor, unless you have another II+ for testing.
