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Circuit/System Testing

  1. Ignition OFF, disconnect the X2 harness connector at the Radio/HVAC display.
  2. Reconnect the Radio/HVAC Control, if disconnected.
  3. Test for less than less than 20 Ω between the ground circuit terminal 2 and ground.
    • If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Test for 6kΩ - 13.5kΩ between the display position circuit terminal 5 and ground.
    • If less than the specified range, test the circuit for a short to ground. If the circuit tests normal, replace the radio.
    • If greater than the specified range, test the circuit for an open/high resistance. If the circuit tests normal, replace the radio.
  5. Ignition ON, verify a test lamp illuminates between the B+ circuit terminal 1 and ground.
    • If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  6. Verify a test lamp illuminates between the remote enable circuit terminal 3 and ground.
    • If the test lamp does not illuminate, test the enable circuit for an open/high resistance.
  7. Test for less than 1 V between the display position signal circuit terminal 5 and ground.
    • if greater than the specified range, test the position signal circuit for a short to voltage. If the circuit tests normal, replace the radio.
  8. Connect a DMM between the display control circuit terminal 4 and ground. Press and release the NAV button on the Radio/HVAC Control. Verify the voltage changes each time the display button is pressed. The value should change between less than 1 V to greater than 4 V.
    • If the value is always less than 1 V, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the radio.
    • If the value is always greater than 1 V, test the control circuit for a short to voltage. If the circuit tests normal replace the radio.
  9. If all circuits test normal, replace the Radio/HVAC display actuator.
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