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Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the inside rearview mirror.
  2. Ignition 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. Connect a test lamp between the inoperative LED signal circuit and the ground circuit terminal 8.
  4. Command the appropriate LED ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
    • If the test lamp is always ON, test the inoperative signal circuit for a short to voltage. If the circuit tests normal, replace the VCIM.
    • If the test lamp is always OFF, test the inoperative 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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