Rear or downstream O2 sensor

DTC code P0141 “O2 heater circuit. Bank 1. Sensor 2” does not even describe what is wrong with the heater circuit. It simply says that there is a problem with the heater circuit; that’s all. It doesn’t say that there is a failure inside the O2 sensor. If this code is the only thing the dealer has, then, it’s a wild jump to the conclusion that the O2 sensor has failed.
Kuiama, you have the wrong repairer. Your repairer doesn’t have s/his facts straight on the other statements, either.
The problem with the O2 heater circuit could be with the supply voltage to it, or, somewhere else.
DTCs (Diagnostic Trouble Codes) do NOT refer to parts, or components. DTCs refer to voltage values. Yes, voltage values in component circuits.
Billions of dollars a year are spent to replace good parts because mechanics and managers aren’t making the distinction between a voltage value and a component.
If the repairer replaces the O2 sensor, based solely on the trouble code, that will negate everything I say, won’t it? Or will it show that there is such a thing as blind luck?