CTS 2003-2005

Open Circuits


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Fig. The infinite reading on this multimeter indicates that the circuit is open

This test already assumes the existence of an open in the circuit and it is used to help locate the open portion.

  1. Isolate the circuit from power and ground.
  3. Connect the self-powered test light or ohmmeter ground clip to the ground side of the circuit and probe sections of the circuit sequentially.
  5. If the light is out or there is infinite resistance, the open is between the probe and the circuit ground.
  7. If the light is on or the meter shows continuity, the open is between the probe and the end of the circuit toward the power source.