Pathfinder LE 2WD V6-3.5L (VQ35) (2001)
The heated oxygen sensor 2 (rear), after three way catalyst, monitors the oxygen level in the exhaust gas on each bank.
Even if switching characteristics of the heated oxygen sensor 1 (front) are shifted, the air fuel ratio is controlled to stoichiometric, by the signal from the
heated oxygen sensor 2 (rear). This sensor is made of ceramic zirconia. The zirconia generates voltage from approximately 1 V in richer conditions to 0
V in leaner conditions.
Under normal conditions the heated oxygen sensor 2 (rear) is not used for engine control operation.
HEATED OXYGEN SENSOR 2 HEATER (REAR) (BANK 1) / (BANK 2)
System Description
The ECM performs ON/OFF control of the heated oxygen sensor 2 heaters (rear) corresponding to the engine speed.