Passport EX 2WD V6-3.2L SOHC (6VD1) (1997)
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into harmless water vapor and carbon dioxide. The catalyst also reduces NOx by converting it to nitrogen.
The Powertrain Control Module (PCM) can monitor this process using the Bank 1 HO2S 2 and the Bank 1 HO2S 3 heated oxygen sensors. The
Bank 1 HO2S 2 sensor produces an output signal which indicates the amount of oxygen present in the exhaust gas entering the three-way catalytic
converter. The Bank 1 HO2S 3 sensor produces an output signal which indicates the oxygen storage capacity of the catalyst. This indicates the
catalyst's ability to efficiently convert exhaust gases. If the catalyst is operating efficiently, the Bank 1 HO2S 2 signal will be more active than the
signal produced by the Bank 1 HO2S 2 sensor.
The catalyst monitor sensors operate the same as the fuel control sensors. The Bank 1 HO2S 3 sensor's main function is catalyst monitoring, but it
also has a limited role in fuel control. If the sensor output indicates a voltage either above or below the 450 mV bias voltage for an extended
period of time, the PCM will make a slight adjustment to fuel trim to ensure that fuel delivery is correct for catalyst monitoring.
A problem with the Bank 1 H02S 2 signal circuit will set DTC P0157, P0158, or P0160 depending on the specific condition. A fault in the heated
oxygen sensor heater element or its ignition feed or ground will result in lower oxygen sensor response. This may cause incorrect catalyst monitor
diagnostic results. A fault in the Bank 1 HO2S 3 heater circuit will cause DTC P0147 to set.
(1) Bank 1 Sensor 1 (Fuel Control)
(2) Bank 1 Sensor 2 (Catalyst Monitor)
(3) Catalytic Converter
(4) Bank 1 Sensor 3 (Catalyst Monitor)
(5) Bank 2 Sensor 1 (Fuel Control)
