Oxygen Sensor: Description and Operation

Heated Oxygen Sensor (HO2S):

DESCRIPTION
The Heated Oxygen Sensor (HO2S) works in the same manner as the non-heated oxygen sensor. The exception is the B+ is supplied to a heating unit that is part of the sensor itself. The heater helps the control module control the fuel injection sooner for better fuel emissions. There are no Diagnostic Trouble Code (DTC)(s) to detect if the heater part of the sensor is working. To check the heater, refer to Function Check in applicable DTC chart. Testing and Inspection

OPERATION
If the heated oxygen sensor pigtail wiring, connector or terminal is damaged, the entire oxygen sensor assembly must be replaced. Do not attempt to repair the wiring, connector or terminals. In order for the sensor to function properly, it must have provided to it a clean air reference. This clean air reference is obtained by way of the oxygen sensor signal and heater wires. Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air reference and degraded oxygen sensor performance.