Oscilloscope Patterns and Waveforms

Idle Air Control Motor Waveform:

1. Connect the probe to each oscilloscope pick-up point as shown in the circuit diagram.
2. Start the engine.
3. When the air conditioning switch is turned "ON", the idling speed increases to operate the idle speed control. Check the instantaneous waveform.

NOTE: Keep in mind that the waveform can be observed only when idle speed control is in operation.