So, transmission acting funny and not able to connect to the ecu, also is an intermittent issue that first presented itself after a long drive. It's cold where you are and there is snow on the ground.
I would start considering bad ground, loose wires/corroded wires, being an older Honda increases the likelihood of speaker wire being used for a previous repair... Maybe in an area that also affects the signal going to the transmission controller indicating which gear is selected, perhaps the transmission was in neutral when this all occured?
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