Circuit Description
WARNING: This page is about a different car, the 2002 GMC Sonoma and 2002 Chevrolet S10 Pickup. However, it is still accessible from the selected car via links, so may be relevant.
The Heated Oxygen Sensor (HO2S) 2, located in the exhaust stream past the Three-Way Catalytic Converter (TWC), produces an output signal relative to the oxygen storage capacity of the TWC. The Powertrain Control Module (PCM) can then determine the ability of the TWC to convert the exhaust emissions effectively. The HO2S 2 signal will be far less active than the signal produced by the front Oxygen Sensor (O2S) 1.