I have been throwing code P0140 for awhile now, and have been planning on swapping out my rear O2s to see whether or not it is the sensor or the cat.

Tonight, my SES light came back on so I scanned it to see what is up. I am now also throwing code P0141. Since both codes are related to the 1 sensor, is it pretty safe to assume that it is indeed the sensor that is at fault? Or should I still swap them out to see if the code follows it? I'd rather just buy a sensor and throw it in there than swap them around and wait for my PCM to throw a different code, if I can avoid it.

Just in case people don't know or don't want to look them up, P0140 is no activity bank 1 sensor 2 and P0141 is O2 sensor circuit malfunction bank 1 sensor 2.

 

Basically that code tells you were the problem is, not always WHAT the problem is. The problem is in your B1S2 circuit...now you just gotta find it

 

Any other ideas? I'm just thinking that since both codes are related to that 1 sensor, that it is probably indeed the sensor at fault.

 

Just to clarify the meaning of the codes...

P0140 sets when the O2 sensor voltage stays between 391-491mV for 1450 samples out of a series of 1500 samples. This is the voltage you will get when the sensor is attached but not operating. It is basically reflecting the PCM bias voltage.

P0141 is specifically for the O2 sensor heater circuit. The sensor is not achieving the required threshhold voltage in the required period of time after a cold start.

It is possible BOTH problems are the result of the sensor not heating up. Once again, could be a faulty sensor, could be a faulty heater power supply.... sensor or the harness.

Since you apparently don't want to be bothered with swapping and waiting, why don't you just replace it and see what happens. Its a 50% shot. Not much more that anyone could suggest here.