The O2 Oxygen Sensor front (O2 1) is located in the exhaust manifold and its function is to detect the amount of oxygen in the exhaust gas, this in comparison with the outside air. This sensor has a tube made of zirconium ceramic, which is closed at one end. This material helps the voltage generated is approximately 1V in richer conditions and 0V in the lowest.
The PCM (Powertrain Control Module) generates a reference voltage of ± 450 MV in the signal circuit of the oxygen sensor. When the Powertrain Control Module (PCM) determines that the time necessary for the sensor to warm up is greater than 1 minute or that the voltage is not within 391-49 mV, this interprets it to be that the sensor is inactive or open and the DTC code P0134 is established.