Does engine code P0140 on a 2001 mazda protege es mean that the O2 sensor needs replacing?

Question

Diagnostic trouble code said O2 sensor circuit no activity detected bank 1 sensor 2

Answer 1

P0140 02 sensor Bank 1 Sensor 2

This code is for the downstream 02 sensor or the catalytic monitor sensor, either the 02 sensor has poor connection or just non opernational. The ECM gives the 02 voltage and the rear just does not respond , it does mean it need to be replaced.