There is some obvious corrosion on the data line traces by the 74LS08 chip
next to the battery. This battery wasn’t replaced until after the old one
started leaking, and it doesn’t look like anything was done to neutralize the
alkaline liquid from the battery. The corrosion is probably still
spreading.
Don B.
Sent: Friday, July 13, 2018 3:54 PM
Subject: [PolySix] Re: can't write to memory correctly after battery
repair
I too am troubleshooting the same issue. I had my battery replaced 10-15 yrs ago and all worked well. Now recently my memory bank is all lit up and not functioning. I'm going to clean the board up a bit as maybe it simply got tarnished from being in storage.
Video of what's happening with mine: