I'd wait until Vig gets precise info back to you, but personally I would be be checking for a short, possibly one that caused a fuse to go in the O2 sensor heater circuit. The faults appear to be in the power circuits, not the output circuit of the O2 sensor. While it could be a bad primary O2 sensor, that is a more expensive place to start just replacing parts. I would be looking at the wiring harness to the O2 sensor for chafing, after checking all fuses.

Good luck

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