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Trunk Will Not Open With Keyless Access

Trouble causes: 

CAUTION:
  • Check that there are no other registered access keys inside the trunk.
  • Inspect LAN system according to the basic diagnostic procedure, and make sure that there is no fault.
  • Check that the keyless access function is not stopped.
  • When the access key or keyless access control module is replaced, registration of the immobilizer is required. For the relevant procedures, refer to the "REGISTRATION MANUAL FOR IMMOBILIZER" provided as a separate volume.
  • Before performing diagnosis, refer to "CAUTION" in "General Description". Ref. to KEYLESS ACCESS WITH PUSH BUTTON START SYSTEM (DIAGNOSTICS)>General Description>CAUTION .
  1. CHECK TRUNK OPENER BUTTON  .

    Check that the trunk opens with the driver's seat trunk opener button.

    Does it open normally?

    Yes  : Go to  2 .

    No  : Check the door lock circuit. Ref. to SECURITY AND LOCKS>DOOR LOCK CONTROL SYSTEM>INSPECTION>BASIC INSPECTION .

  2. CHECK KEYLESS OPERATION  .

    Check that the trunk opens when the trunk opener button of the access key is operated.

    Does it open normally?

    Yes  : Go to  7 .

    No  : Go to  3 .

  3. CHECK TRUNK UNLOCK OPERATION  .
    1. Turn the ignition switch to ON.
    2. Using the Subaru Select Monitor, check the following items in the [Active Test] of [Body Control]. Ref. to BODY CONTROL (DIAGNOSTICS)>ACTIVE TEST .
      • R gate/trunk UNLK output
    3. Check that the trunk opens when the R gate/trunk UNLK signal is output.

    Does it open normally?

    Yes  : Go to  7 .

    No  : Go to  4 .

  4. CHECK HARNESS (OPEN CIRCUIT)  .
    1. Turn the ignition switch to OFF.
    2. Disconnect the body integrated unit connector and trunk lid lock actuator connector.
    3. Measure the resistance between body integrated unit connector and trunk lid lock actuator connector.

      Connector and terminal 

      (i4) No. 7 - (Td47) No. 1:

    Is the resistance less than 10 Ω?

    Yes  : Go to  5 .

    No  : Repair or replace the open circuit of harness.

  5. CHECK WIRING HARNESS  .

    Measure the resistance between the trunk lid lock actuator connector and chassis ground.

    Connector and terminal 

    (Td47) No. 2 - Chassis ground:

    Is the resistance less than 10 Ω?

    Yes  : Go to  6 .

    No  : Repair or replace the open circuit of harness.

  6. CHECK TRUNK LID LOCK ACTUATOR  .

    Check the trunk lid lock actuator. Ref. to SECURITY AND LOCKS>TRUNK LID LATCH AND ACTUATOR ASSEMBLY .

    Is trunk lid actuator normal?

    Yes  : Replace the body integrated unit. Ref. to BODY CONTROL/COMMUNICATION SYSTEM>BODY INTEGRATED UNIT .

    No  : Replace the trunk lid latch and actuator assembly. Ref. to SECURITY AND LOCKS>TRUNK LID LATCH AND ACTUATOR ASSEMBLY .

  7. CHECK ACCESS KEY  .

    Check the access key LED when the trunk opener button of the access key is operated.

    Does the access key LED illuminate?

    Yes  : Go to  8 .

    No  : Replace the access key. Ref. to SECURITY AND LOCKS>ACCESS KEY>REPLACEMENT .

  8. CHECK ACCESS KEY  .
    1. Prepare all access keys registered to the vehicle.
    2. Check that the trunk opens with each access key.

    Does it open normally?

    Yes  : Go to  9 .

    No  : Replace the access key. Ref. to SECURITY AND LOCKS>ACCESS KEY>REPLACEMENT .

  9. CHECK DATA MONITOR  .
    1. Turn the ignition switch to ON.
    2. Using the Subaru Select Monitor, check the following items in the [Data Monitor] of [Keyless Access with Push Button Start(Collation)]. Ref. to Keyless Access With Push Button Start System (Diagnostics)>Data Monitor .
      • Trunk Request SW
    3. Read the data when pressing the trunk opener button.

    Does the data display [ON]?

    Yes  : Go to  13 .

    No  : Go to  10 .

  10. CHECK HARNESS (OPEN CIRCUIT)  .
    1. Turn the ignition switch to OFF.
    2. Disconnect the trunk opener button connector and the keyless access control module connector.
    3. Using a tester, measure the resistance between the trunk opener button connector and the keyless access control module connector.

      Connector and terminal 

      (Td31) No. 1 - (i91) No. 17:

    Is the resistance less than 10 Ω?

    Yes  : Go to  11 .

    No  : Repair or replace the open circuit of harness.

  11. CHECK HARNESS (OPEN CIRCUIT)  .
    1. Using a tester, measure the resistance between the trunk opener button connector and chassis ground.

      Connector and terminal 

      (Td31) No. 2 - Chassis ground:

    Is the resistance less than 10 Ω?

    Yes  : Go to  12 .

    No  : Repair or replace the open circuit of harness.

  12. CHECK TRUNK OPENER BUTTON  .

    Using a tester, measure the resistance between the trunk opener button connector terminals.

    Terminals 

    No. 1 - No. 2:

    Is the resistance less than 10 Ω when switch is pushed?

    Yes  : Go to  13 .

    No  : Replace the trunk opener button.

  13. CHECK HARNESS (OPEN CIRCUIT)  .
    1. Turn the ignition switch to OFF.
    2. Disconnect the exterior rear antenna connector and the keyless access control module connector.
    3. Using a tester, measure the resistance between the exterior rear antenna connector and keyless access control module connector.

      Connector and terminal 

      (Td33) No. 1 - (i92) No. 8:

      (Td33) No. 3 - (i92) No. 7:

    Is the resistance less than 10 Ω?

    Yes  : Go to  14 .

    No  : Repair or replace the open circuit of harness.

  14. CHECK OUTSIDE REAR ANTENNA  .

    Replace the outside rear antenna with new or properly working parts.

    Does it operate properly?

    Yes  : Replace the outside rear antenna. Ref. to SECURITY AND LOCKS>KEYLESS ACCESS OUTDOOR ANTENNA>REMOVAL .

    No  : Go to  15 .

  15. CHECK KEYLESS ACCESS SYSTEM CHECK  .
    1. Turn the ignition switch to ON.
    2. Using the Subaru Select Monitor, check the following items in the [Keyless Access with Push Button Start Check] of [Keyless Access with Push Button Start(Collation)]. Ref. to Keyless Access with Push Button Start System (Diagnostics)>Keyless Access With Push Button Start Check .
    • Out of trunk transmitter + room tuner

    Does the outside buzzer sound?

    Yes  : The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

    NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

    No  : Replace the keyless access control module. Ref. to SECURITY AND LOCKS>KEYLESS ACCESS CONTROL MODULE .

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