0 PEAK-PEAK Indicates the difference in voltage between the lowest and the highest value of the displayed waveform.

0 This screen displays the measured resistance in ohms (£2).

Fig. 6.14 Voltage trace from a stepper motor test by operating it with the diagnostic tool connected to the serial communication port of the ECM. An oscilloscope can also be used to check the pulses that are sent to the motor from the ECM. Figure 6.14 gives an impression of the type of result that is to be expected from the PMS 100 oscilloscope when used to test a stepper motor.

Fig. 6.16 Checking an idle speed air valve
Do It Yourself Car Diagnosis

Do It Yourself Car Diagnosis

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