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Rear Heated Oxygen Sensor (HO2S 2)

Description
The Heated Oxygen Sensor 2 (HO2S 2), located in the exhaust stream past the catalytic converter produces an output signal relative to the oxygen storage capacity of the catalytic converter. The Powertrain Control Module (PCM) can then determine the catalytic converter's ability to convert exhaust emissions effectively. The HO2S 2 signal will be far less active than the signal produced by the front Oxygen Sensor 1 (O2S 1).