[Citroënbender]

Unfortunately, no smoking gun. There was a little oxidisation haze from water drips, but it came off with careful dry brushing.

I had a quick look at the referred forum, it may be an option.

My problem is somewhere in the “middle”. I can drive the faulty circuits with actuator tests, and the inputs to the board are all correct. A number of the input status lines are being misread, and that’s the main issue.