P0155, replaced O2 sensor, but still have MIL on, what else could it be and how do I test for that?

Question

2002 S10 Blazer LS, replaced the O2 sensor, verified that the fuse is fine for O2 sensors, Pro OBD II reader shows that the O2 sensor is operating normally, cleaned MAF wires with MAF cleaner, cleared code, but still getting problem.

Answer 1

P0155 0 02 sensor heater circuit malfunction  Bank 2 Sensor 1

This code is for the heater circuit , the heater circuit of the 02 sensor is used to maintain operating temperature, the 02 sensor does not measure oxygen what it does is measure heat, this represent the oxygen, The way to fix the problem is use a test light , disconnect the bank 2 sensor 1 02 sensor with the engine off , ignition on. you should have power from the heater circuit, if there is none you would need further inspection up to the ECM.also keep in mind just where the ECM is located water intrusion can make its way in there creating corrosion.