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Circuit/System Testing

    NOTE:

    The A24P passenger exterior door handle assembly has two harness connectors. Of these two harness connectors, make sure that only the T10N passenger door handle keyless entry antenna harness connector is disconnected. Disconnecting both harness connectors will result in the inability to activate the antenna and cause an improper diagnosis.

  1. Ignition OFF, disconnect the harness connector at the T10N passenger door handle keyless entry antenna, ignition ON.
  2. Test for less than 1 V between the signal circuit terminal 1 and ground.
    • If 1 V or greater 
    1. Ignition OFF, disconnect the harness connector at the K84 keyless entry control module, ignition ON.
    2. Test for less than 1 V between the signal circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K84 keyless entry control module.
    • If less than 1 V 
    3. NOTE:

    When using the MIN MAX function, autorange on the DMM may not function properly. To ensure accurate test results, turn off autorange and manually set the DMM range to 000.0 V.

  3. Ignition OFF, install a DMM between the signal circuit terminal 1 and ground. Set the DMM to capture DC voltage using the MIN MAX function. Turn off autorange and manually set the DMM range to 000.0 V.
  4. Lock the vehicle doors using the keyless entry transmitter. Activate the antenna by operating the driver release handle.
  5. Verify the MAX voltage captured by the DMM is greater than 1 V.
    • If 1 V or less 
    1. Ignition OFF, disconnect the harness connector at the K84 keyless entry control module.
    2. Test for infinite resistance between the signal circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
    3. Test for less than 2 Ω in the signal circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K84 keyless entry control module.
    • If greater than 1 V 
  6. Test for less than 1 V between the low reference circuit terminal 2 and ground.
    • If 1 V or greater 
    1. Ignition OFF, disconnect the harness connector at the K84 keyless entry control module, ignition ON.
    2. Test for less than 1 V between the low reference circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K84 keyless entry control module.
    • If less than 1 V 
    7. NOTE:

    When using the MIN MAX function, autorange on the DMM may not function properly. To ensure accurate test results, turn off autorange and manually set the DMM range to 000.0 V.

  7. Install a DMM between the signal circuit terminal 1 and the low reference circuit terminal 2. Set the DMM to capture DC voltage using the MIN MAX function. Turn off autorange and manually set the DMM range to 000.0 V.
  8. Lock the vehicle doors using the keyless entry transmitter. Activate the antenna by operating the driver release handle.
  9. Verify the MAX voltage captured by the DMM is greater than 1 V.
    • If 1 V or less 
    1. Ignition OFF, disconnect the harness connector at the K84 keyless entry control module.
    2. Test for infinite resistance between the low reference circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
    3. Test for less than 2 Ω in the low reference circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K84 keyless entry control module.
    • If greater than 1 V 
  10. Replace the T10N passenger door handle keyless entry antenna.
  11. Lock the vehicle doors using the keyless entry transmitter. Activate the antenna by operating the driver release handle.
  12. Verify DTC B3120 is not set.
    • If DTC B3120 is set 

      Replace the K84 keyless entry control module.

    • If DTC B3120 is not set 
  13. All OK.
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