Arthur - is it time for me to do the test feed through the relay socket you mentioned above or continue looking for other possible faults?
One item that occurred to me yesterday was that I may have turned the car off while it was still in drive the last time I drove into the garage; I recalled not being able to remove the key and then I realized it was not in park. Other than putting the gear shift lever in Park and removing the key, I don't recall anything else "unusual" about the shut down.
Socks

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SocksE420
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