Oscilloscope Patterns and Waveforms

Waveform




If you release the accelerator pedal suddenly after engine running about 4000 rpm, fuel supply will stop for short period and the O2 sensor service data in the Hi-Scan (Pro) will display values 200mV or lower. When you suddenly press on the accelerator pedal down, the voltage will reach 0.6 - 1.0 V.
When you let the engine idle again, the voltage will fluctuate between 200 mV or lower and 0.6 - 1.0 V.
In this case, the O2sensor can be determined as good.