DTC P0133 & P0153: Ho2S Circuit - Slow Response - Bank 1 & 2, Sensor 1: 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) continuously monitors the Heated Oxygen Sensor (HO2S) activity for 60 seconds. During the monitoring period, the PCM counts the times that the HO2S responds from rich to lean and from lean to rich, and adds the time it took to complete all transitions. With this information, the PCM can determine the average time for all transitions. If the average response time is too slow, a DTC sets. The PCM determines the lean to rich transition when the HO2S voltage changes from less than 300 mV to more than 600 mV. The PCM determines the rich to lean transition when the HO2S voltage changes from more than 600 mV to less than 300 mV. If the HO2S responds too slowly a DTC will set.