It's not running, but the last time it was, January 2022, the charging system was 100%. As an engineer, I my immediate reaction is to look for "what changed" that cause the problem, so my focus was on anything that could be different in the three weeks since the last engine start, such as dead battery or a "hidden" fuse that suddenly blew when I hit the starter. I'm not averse to replacing parts until the problem is solved, but that can get expensive (maybe not in this case) and I'd like to actually diagnose the problem to the extent possible before doing so.