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Oscilloscope Patterns and Waveforms

Inspection Using An Oscilloscope (Reference)




HO2S (front) signal
PCM terminals
- 1AB (+) - 2H (-)

Oscilloscope setting
- 0.1 V/DIV (Y), 400 ms/DIV (X), DC range

Vehicle condition
- Idle after warm up (engine speed approx. 700 rpm, no load, P/S off, A/C off)




HO2S (front) heater control signal PCM terminals
- 4A (+) - 1C (-)

Oscilloscope setting
- 4 V/DIV (Y), 200 ms/DIV (X), DC range

Vehicle condition
- Idle after warm up (engine speed approx. 700 rpm, no load, P/S off, A/C off)
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