Inspection Using Oscilloscope

Primary Signal Of Ignition Coil - Run engine at idle speed. Connect the probe to oscilloscope pick-up point No. 1 as shown in circuit diagram. See Figure . Primary signal should be as illustrated. See Fig 1 .

Fig 1: Primary Signal Waveform
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Control Signal Of Power Transistor - Connect the probe to oscilloscope pick-up point No. 2 as shown in circuit diagram. See Figure . Power transistor control signal should be as illustrated. See Fig 2 .

Fig 2: Power Transistor Control Signal Waveform
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