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Oscilloscope Patterns and Waveforms

Inspection Using An Oscilloscope (Reference)

NOTE: The duty ratio for the wave pattern can vary with the control conditions. Therefore determine comprehensively where the malfunction occurs among the input systems, output systems, and the PCM,

Front HO2S heater control




- Terminal connected: 1V (+) - Negative battery terminal
- Oscilloscope setting: 5 V/DIV (Y): 50 ms/DIV (X), DC range
- Measurement condition: Idling after warm-up (no load)