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Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the cellular microphone.
  2. Ignition ON, test for greater than 9 volts between the signal circuit terminal B and ground.
    • If less than specified value, test the cellular microphone signal circuit for a short to ground, open/high resistance. If the circuit tests normal, replace the VCIM.
  3. Test for greater than 9 volts between the cellular microphone signal circuit terminal B and the drain circuit terminal A.
    • If less than specified value, test the drain wire for an open/high resistance. If the circuit tests normal, replace the VCIM.
  4. If all circuit test normal, test or replace the cellular microphone assembly.
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