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Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector X3 at the appropriate door switch.
  2. Ignition ON, verify a test lamp does not illuminate between the following circuit terminals and ground:
    • 5-volt reference circuit terminal A2
    • Signal circuit terminal A5
    • Signal circuit terminal A6
    • Low reference circuit terminal A4
    • If the test lamp illuminates, test the appropriate circuit for a short to voltage.
  3. Ignition OFF, test for infinite resistance between the following circuits and ground:
    • 5-volt reference circuit terminal A2
    • Signal circuit terminal A5
    • Signal circuit terminal A6
    • Low reference circuit terminal A4
    • If less than the specified value, test the appropriate circuit for a short to ground.
  4. Test for 4K-7K ohms of resistance between the 5-volt reference circuit terminal A2 and the low reference circuit terminal A4.
    • If not within the specified range, test the 5-volt reference circuit and the low reference circuit for an open/high resistance. If the circuits test normal, test or replace the rearview mirror motor.
  5. Test for 1K-7K ohms of resistance between the 5-volt reference circuit terminal A2 and the signal circuit terminal A5.
    • If not within the specified range, test the signal circuit for an open/high resistance. If the circuits test normal, test or replace the rearview mirror motor.
  6. Test for 1K-7K ohms of resistance between the 5-volt reference circuit terminal A2 and the signal circuit terminal A6.
    • If not within the specified range, test the signal circuit for an open/high resistance. If the circuits test normal, test or replace the rearview mirror motor.
  7. If all circuits test normal, replace the appropriate door module.