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Home >> Toyota >> 2013 >> Prius Plug-in >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 103 (Power Door Lock Control System (Diagnostics & Symptom Tests) (Except Plug-In)) >> Power Door Lock Control System >> Symptom Tests >> Only Back Door cannot be Opened >> Procedure
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Only Back Door cannot be Opened: Procedure

WARNING: This page is about a different variant/trim than selected.
  1. SYSTEM CHECK 
    1. Check the vehicle specification.

      Result

      Result Proceed to
      w/o Entry System Back Door Open Function A
      w/ Entry System Back Door Open Function B

    B → See step   6 

    A: Go to next step 

  2. CHECK POWER DOOR LOCK OPERATION (BASIC FUNCTION) 
    1. Check the power door lock basic function. Refer to OPERATION CHECK .

      OK

      The power door lock basic functions operate normally.

    NG → See step   14 

    OK: Go to next step 

  3. READ VALUE USING TECHSTREAM (DOOR LOCK STATUS) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Main Body / Data List.
    5. Read the Data List according to the display on the Techstream.
      MAIN BODY (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU))

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Back Door Open Back door lock/Permit or Prohibt Permit: Back door unlocked
      Prohibt: Back door locked
      -

      OK

      The Techstream indicates Permit or Prohibit according to the door lock operation shown in the table.

    NG → See step   15 

    OK: Go to next step 

  4. PERFORM ACTIVE TEST USING TECHSTREAM 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Main Body / Active Test.
    5. Perform the Active Test according to the display on the Techstream.
      MAIN BODY (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU))

      Tester Display Test Part Control Range Diagnostic Note
      Trunk and Back-Door Open Operate back door lock motor ON or OFF -

      OK

      The back door lock assembly unlatches when ON is selected.

    NG → See step   6 

    OK: Go to next step 

  5. READ VALUE USING TECHSTREAM 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Main Body / Data List.
    5. Read the Data List according to the display on the Techstream.
      MAIN BODY (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU))

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Back Door Open Handle SW Back door opener switch signal/ON or OFF ON: Back door opener switch pushed
      OFF: Back door opener switch not pushed
      -

      OK

      The Techstream indicates ON or OFF according to the switch operation shown in the table.

    NG → See step   10 

    OK → See step   15 

  6. INSPECT BACK DOOR LOCK ASSEMBLY 
    1. Remove the back door lock assembly. Refer to REMOVAL .
      Fig 1: Inspecting Back Door Lock Assembly
      GTY216939Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check the operation of the door lock motor.
      1. Move the door lock to the lock position.
      2. Apply battery voltage to the door lock motor and check the operation of the door lock motor.

        OK

        Connection Result
        Battery positive (+) → Terminal 4 (ACT+)
        Battery negative (-) → Terminal 3 (ACT-)
        Unlocks
    3. Check the operation of the door courtesy switch.
      1. Measure the resistance according to the value(s) in the table below.

        Standard Resistance

        Tester Connection Switch Condition Specified Condition
        1 (E) - 2 (+) Locked 10 kΩ or higher
        1 (E) - 2 (+) Unlocked Below 1 Ω
        TEXT IN ILLUSTRATION

        *1 Component without harness connected
        (Back Door Lock Assembly)
        *2 Lock
        *3 Unlock

    NG → See step   12 

    OK: Go to next step 

  7. CHECK HARNESS AND CONNECTOR (BACK DOOR LOCK ASSEMBLY - MAIN BODY ECU) 
    1. Disconnect the main body ECU (multiplex network body ECU) connector.
      Fig 2: Identifying Main Body ECU (Multiplex Network Body ECU) Connector
      GTY227351Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the instrument panel junction block assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      R18-4 (ACT+) - 2D-9 (TR+) Always Below 1 Ω
      R18-4 (ACT+) - Body ground Always 10 kΩ or higher
      R18-2 (+) - L7-19 (BCTY) Always Below 1 Ω
      R18-2 (+) - Body ground Always 10 kΩ or higher
      R18-3 (ACT-) - Body ground Always Below 1 Ω
      R18-1 (E) - Body ground Always Below 1 Ω
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Back Door Lock Assembly)
      *2 Front view of wire harness connector
      (to Instrument Panel Junction Block Assembly)
      *3 Front view of wire harness connector
      (to Main Body ECU (Multiplex Network Body ECU))
      - -

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  8. REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 
    1. Replace the instrument panel junction block assembly. Refer to REMOVAL .

    NEXT: Go to next step 

  9. CHECK BACK DOOR OPEN OPERATION 
    1. Check that the back door can be opened.

      OK

      The back door can be opened normally.

    NG → See step   15 

    OK → END (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY WAS DEFECTIVE) 

  10. INSPECT BACK DOOR OPENER SWITCH ASSEMBLY 
    1. Remove the back door opener switch assembly. Refer to REMOVAL .
      Fig 3: Identifying Back Door Opener Switch Assembly
      GTY217188Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check the operation of the opener switch.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      2 (E) - 3 (UL) Back door opener switch not pushed 10 kΩ or higher
      2 (E) - 3 (UL) Back door opener switch pushed Below 1 Ω
      TEXT IN ILLUSTRATION

      *1 Component without harness connected
      (Back Door Opener Switch Assembly)

    NG → See step   13 

    OK: Go to next step 

  11. CHECK HARNESS AND CONNECTOR (BACK DOOR OPENER SWITCH ASSEMBLY - MAIN BODY ECU) 
    1. Disconnect the main body ECU (multiplex network body ECU) connector.
      Fig 4: Identifying Main Body ECU (Multiplex Network ECU) Connector
      GTY233628Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      V4-3 (UL) - L7-23 (BDSU) Always Below 1 Ω
      V4-3 (UL) - Body ground Always 10 kΩ or higher
      V4-2 (E) - Body ground Always Below 1 Ω
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Back Door Opener Switch Assembly)
      *2 Front view of wire harness connector
      (to Main Body ECU (Multiplex Network Body ECU))

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   15 

  12. REPLACE BACK DOOR LOCK ASSEMBLY. Refer to  REMOVAL 
  13. REPLACE BACK DOOR OPENER SWITCH ASSEMBLY. Refer to  REMOVAL 
  14. GO TO PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE  
  15. REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to  REMOVAL