Need help fixing A4000

[Plaz]

A couple years ago I acquired an A4000 with fairly typical battery acid damage

Yes a dead CIA can zombie the system. In many cases you'll notice one running much hotter that the other. Seen it a couple of times. The more typical CIA failure lets the system boot and just keeps the floppy from working. Did any of the battery damage make it over to the sim sockets... even a little? I've seen that cause rot under sockets also leading to problems.

Plaz

[Plaz]

However, generally the amiga will boot with a bad cia no?

Generally yes, but there are always exceptions. I've repaired one 2000, one 3000, two 1200's and one 4000 in the past that would not boot at all because of a dead CIA. A small percentage of my total repairs for sure, but still possible.

If there is no screen flicker or color at power on, I'm also very suspicious of the health of the CPU. Also make sure the CPU jumpers are set properly. A search should turn that info up quickly.

Plaz