DTC P0140 & P0160: Ho2S Circuit - Insufficient Activity - Bank 1 & 2, Sensor 2: Description

WARNING: This page is about a different car, the 2002 Chevrolet Corvette. However, it is still accessible from the selected car via links, so may be relevant.

The Powertrain Control Module (PCM) supplies a voltage of approximately 450 mV between the Heated Oxygen Sensor (HO2S) high and low signal circuits. The oxygen (O2) sensor varies the voltage from approximately 1,000 mV when the exhaust is rich, through approximately 10 mV when the exhaust is lean. The PCM monitors and stores the Heated Oxygen Sensor (HO2S) voltage information. The PCM evaluates the HO2S voltage samples in order to determine the period of time during which the HO2S voltage was out of range. The PCM compares the stored HO2S voltage samples taken within each sample period, and determines if the majority of the samples are out of the operating range. The PCM monitors the HO2S voltage and detects if the voltage goes out of the bias range. If the PCM does not detect that the voltage went out of the bias range, a DTC sets.