The Oxygen Sensors send information to the Power Train Control Module (PCM) to determine the amount of oxygen found in the exhaust system. This code refers to bank 1, sensor 2, which is the second sensor located in bank number 1. With the information that the Oxygen Sensor sends to the PCM (Powertrain Control Module), the functioning of the TWC (catalytic converter) is also checked.
It should be noted that the Oxygen Sensors (O2) include a heating element, which is controlled by the PCM to heat the O2 to the temperature necessary for operation. This with the aim of reducing emissions and entering more quickly in closed circuit.
The PCM constantly monitors the heater circuits in order to locate voltages outside the expected range. If the PCM detects that there is a voltage condition below the normal range, the DTC code P0037 OBD2 is set.