[jb92563]

Since O2 sensors don't go bad often its more cost and time effective to take the sensor from the other good side and swap sides to see if the code comes back on the other bank.

If the code does repeat but on the other bank then the O2 sensor replacement is warranted otherwise its most likely to be something else, like a wiring or dirty connector issue.

The before and after cat O2 sensors are definitely different so don't make substitutions if you want your codes to be resolved.

Testing the heater circuit for continuity may work if you know the sensor connector pinout details.