HO2S Bank 1 Sensor 2

The scan tool range is 0-1275 mV (0-1.275 volts). This parameter indicates the output voltage for HO2S bank 1 sensor 2 (post catalyst oxygen sensor). The voltage should fluctuate within a range between about 50 mV (lean exhaust) and 800 mV (rich exhaust) while operating in Closed Loop. The post-catalyst HO2S output voltage will fluctuate slowly over a longer period of time, compared to the fuel control oxygen sensors. This is due to the oxygen storage capacity of an efficiently operating catalyst.