Thanks Jack and Uwe. In reading the Bentley and other TCU/TCM information they indicated one possibility for not being able to communicate might identified on the ECM end. I may have meant voltage in my first post. Uwe, your recommendation seems a good possibility (which is what I was trying to ferret out), i.e., other modules can't communicate either.
Thinking through... don't all modules communicate through the ECM or do they have individual paths?
Waiting for Bentley to respond with a reactivation code for my manual so I can pull the wiring diagrams. I'm learning more about the ECM and TCU than I ever thought I wanted, but it will give me something to do between beers and BBQs. I'll keep the post updated with my endeavors.
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