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Circuit/System Testing

  1. Ignition OFF, disconnect the inside rearview mirror harness connector .
  2. Ignition ON, test for 9.2 to 10.2 volts on the keypad supply voltage circuit.
    • If less than the specified voltage repair short to ground or open or replace the VCIM.
  3. Test for less than 1 ohm between the inside rearview mirror harness connector terminal 8 and ground.
    • If greater than specified value repair open or high resistance.
  4. Connect a DMM between the inside rearview mirror harness connector terminal 14 and ground. With a scan tool command the green LED ON. Verify 9.2 to 10.2 volts is present with the green LED commanded ON.
    • If 9.2 to 10.2 volts is present with the green LED is commanded ON, replace the inside rearview mirror.
  5. Connect a DMM between the inside rearview mirror harness connector terminal 15 and ground. With a scan tool command the green LED ON. Verify 9.2 to 10.2 volts is present with the red LED commanded ON.
    • If 9.2 to 10.2 volts is present with the red LED is commanded ON, replace the inside rearview mirror.
  6. Disconnect the VCIM harness connector C1.
  7. Test for less than 1 volt between the C1 VCIM connector terminal 3 and the inside rearview mirror harness connector terminal 14.
    • If more than the specified value repair short to voltage on the keypad green LED signal circuit.
  8. Test for less than 1 volt between the C1 VCIM connector terminal 2 and the inside rearview mirror harness connector terminal 15.
    • If more than the specified value repair short to voltage on the keypad red LED signal circuit.
  9. Test for less than 1 ohm between the C1 VCIM connector terminal 3 and the inside rearview mirror harness connector terminal 14.
    • If more than the specified value repair open or high resistance on the keypad green LED signal circuit.
  10. Test for less than 1 ohm between the C1 VCIM connector terminal 2 and the inside rearview mirror harness connector terminal 15.
    • If more than the specified value repair open or high resistance on the keypad red LED signal circuit.
  11. If all circuits test normal, test or replace the VCIM.
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