Test Readings, Control Module Connections: Remember

• Observe the test conditions. Use common sense when evaluating test results.
• Unless otherwise stated, the test readings presented are with the ignition switch in the ON position.
• Check the following points:
  • First check that the control module is supplied with current and grounded.
  • Then check all sensor inputs and signals from other systems.
  • Check the control module outputs last. Remember that the test readings do not indicate whether or not the actuator is working.
• If any reading is not OK, consult the wiring diagram to trace the leads, connectors or components which ought to be checked more thoroughly.
• The test readings given apply to a correctly calibrated Fluke 88/97.
• The test readings show the pulse ratio and pulse duration of the signal. A test instrument capable of measuring both pulse ratio and pulse duration must be used.

Fig 1: Identifying Test Readings

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