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Oscilloscope Patterns and Waveforms

Inspection Using An Oscilloscope (Reference) (California emission regulation applicable ATX model)

Ignition coil signal




- PCM terminals
- No.1 cylinder: 102 (+) - 26 (-)
- No.2 cylinder: 78 (+) - 26 (-)
- No.3 cylinder: 103 (+) - 26 (-)
- No.4 cylinder: 104 (+) - 26 (-)

- Oscilloscope setting: 2.5V/DIV (Y), 20 ms/DIV (X), DC range
- Vehicle condition: Idle after warm up (no load)