Diagnostic code P0052 OBD2 refers to the Oxygen Sensor which is located in bank number 2 on the ahead of the catalyst. It should be noted that there is also an O2 (Oxygen Sensor) located on the back of the catalytic converter, but this corresponds to Sensor number 2, bank 2. This Oxygen Sensor (O2) number 1 is also known like an air/fuel ratio sensor, because in some vehicles this is the case.
The function is to detect the oxygen portion in the exhaust gas, in order to compare it to the outside air. This information is then sent to the PCM (Powertrain Control Module) who set the air/fuel ratio entering the engine. The function of this sensor is affected when the temperature of the exhaust gases is low, for this reason this sensor is equipped with a heating element and is activated in order to provide help and, in this way, better readings are obtained from the O2 sensor (Oxygen Sensor).
The DTC code means that the resistance of the heater circuit is above the expected level. In some cases, that resistance level exceeds 10 A to establish the code.