I wasn't being sarcastic, just that this is the sort of thing I get lumbered with too.

Really need a wiring diagram to check all the PCM feeds and grounds. Difficult for me to share the ones I have access to! As they are mostly in sections not the complete 'picture' as it were.

The test you've done does seem a bit conclusive it's a PCM problem.

They maybe able to advise further tests before condemning the PCM?