Mitsubishi Montero Sport LS 3.0 P0136 and P0141 need help

I have a montero Sport ls 3.0 with P0136 bank 1 sensor 2 and P0141 bank 1 sensor 2 error. when i scanned it it shows me with 4 error codes two on each P0136 and P0141 bank 1 sensor 2 with pending and without pending. Can someone tell me where is P0136 bank 1 sensor 2 and P0141 bank 1 sensor 2. Plus what is the meaning of pending on this codes. Thank you for any help.

I looked in the mits service manual on both codes and it was telling me that it is most likely the right rear o-2 sensor or the circuit. whenever I have that code it is the heated o-2 sensor.

The PCM monitors all sensors every time you start the vehicle.

If it detects something is wrong with a sensor, it will remember it. If a sensor sends a fault signal to the PCM too many times in a row (usually 3 times), the PCM will set a "hard" code and the CEL will illuminate.

If the PCM detects a fault less times to set a hard code, it will set a "pending" code. It's kinda like a "heads up, something might be wrong" signal.