Pathfinder 4WD V6-3.3L (VG33E) (1996)
Oxygen Sensor: Diagnostic Trouble Code Tests and Associated Procedures
DTC 0303 Front Heated Oxygen Sensor
Front Heated Oxygen Sensor
DESCRIPTION
The front heated oxygen sensor (left bank) is placed into the front tube (left bank). It detects the amount of oxygen in the exhaust gas compared to the
outside air. The front heated oxygen sensor (left bank) has a closed-end tube made of ceramic zirconia.
Output Voltage / Mixture Ratio
The zirconia generates voltage from approximately 1V in richer conditions to 0V in leaner conditions. The front heated oxygen sensor (left bank)
signal is sent to the ECM. The ECM adjusts the injection pulse duration to achieve the ideal air-fuel ratio. The ideal air-fuel ratio occurs near the
radical change from 1V to 0V.