Test readings, control module connections: Remember

• Note the test conditions and use common sense when assessing the test result.
• The nominal values specified apply with the ignition in the ON position unless otherwise stated.
• First check that the control module has a power supply and is grounded.
• Then check all sensor inputs and signals from other systems.
• Finally, check the outputs. Remember that the test results do not tell us whether or not the module is functioning properly.
• If any reading is not OK, consult the wiring diagram to trace the leads, connectors or components which should be checked more thoroughly.
• The specified test readings refer to those obtained with a calibrated Fluke 88/97.
• Test readings in % (+) and ms (+) show the pulse ratio and pulse duration of the signal. A test instrument capable of giving pulse ratio and pulse width readings must be used. The sign indicates a positive trigger pulse, TRIG+. 

Fig 1: Identifying Multimeter

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