2 thoughts on approaching this come to mind (from a high level):

1) In general, things break one-at-a-time. One root cause may create several different symptoms, leading one to believe there are several different problems, when in fact one solution may solve all of them.

2) In general, truly bizarro electrical behavior (meaning window switch affecting radio, for example) is usually grounding problems. This may be expanded to voltage regulator or computer control problems, but one key missing or weak ground connection can have electricity taking all sorts of weird pathes.

When I'm deep in the weeds thinking a problem is super-complicated, I stop, step back and remind myself that there's got to be a simpler solution than what I'm thinking.

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Mark in MA
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