Pilot 4WD V6-3.5L (2008)
Oxygen Sensor: Description and Operation
Secondary Oxygen Sensor
Secondary Heated Oxygen Sensor (Secondary HO2S)
The secondary HO2S detects the oxygen content in the exhaust gas downstream of the warm up three way catalytic converter (WU-TWC), and sends
signals to the PCM. To stabilize its output, the sensor has an internal heater. The PCM compares the HO2S output with the A/F sensor output to
determine catalyst efficiency. The secondary HO2S is on the WU-TWC.