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Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the inside rearview mirror.
  2. Ignition OFF, doors closed, interior lamps OFF, test for less than 5 ohms between the inside rearview mirror ground circuit terminal 8 and ground.
    • If greater than specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, command the appropriate LED OFF with a scan tool. Test for less than 1 volt between the appropriate LED signal circuit terminal and ground.
    • If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the VCIM.
  4. Command the appropriate LED ON with a scan tool. Test for greater than 9 volts between the appropriate LED signal circuit terminal and ground.
    • If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the VCIM.
  5. If all circuits test normal, replace the inside rearview mirror.
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