LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Toyota >> 2021 >> Land Cruiser Base >> Repair and Diagnosis (Single Page) >> Body & Frame >> Door Locks >> Smart Key System (Keyless Entry) - Symptom Tests (2 Of 2) >> SMART KEY SYSTEM (for Entry Function) >> Back Door Entry Lock Function does not Operate [08/2015 - 08/2017] >> Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Back Door Entry Lock Function does not Operate [08/2015 - 08/2017]: Procedure

  1. CHECK POWER DOOR LOCK CONTROL SYSTEM 
    1. When the door control switch on the multiplex network master switch assembly is operated, check that the doors unlock and lock according to the switch operation (Refer to OPERATION CHECK [08/2015 - ] ).

      OK

      Door locks operate normally.

    Result: 

    NG 

    GO TO POWER DOOR LOCK CONTROL SYSTEM 

    (Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2015 - ] )

    Result: 

    OK 

    See step  2

  2. READ VALUE USING TECHSTREAM (TR/B-DOOR LOCK SW) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Smart Key / Data List.
    5. Read the Data List according to the display on the Techstream.
      SMART KEY

      Tester Display Measurement Item/Display Normal Condition Diagnostic Note
      Tr/B-Door Lock SW Back door opener switch assembly (lock switch) / ON or OFF ON: Back door opener switch assembly (lock switch) pressed
      OFF: Back door opener switch assembly (lock switch) not pressed
      • Displays whether the back door opener switch assembly (lock switch) is on or off.
      • Use this Data List item to help determine if there is a switch malfunction when the back door lock function does not operate.

      HINT: 

      When checking the operation of the entry lock function several times, it can be operated up to 2 times consecutively. To operate the function 3 times or more consecutively, the doors need to be unlocked once. However, this is only for the entry lock function, other door lock operations, such as a wireless door lock operation can be performed consecutively.

      OK

      The Techstream display changes correctly in response to the operation of the back door opener switch assembly.

    Result: 

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 

    (Refer to REMOVAL [08/2015 - ] )

    Result: 

    NG 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (BACK DOOR OPENER SWITCH ASSEMBLY - CERTIFICATION ECU [SMART KEY ECU ASSEMBLY]) 
    1. Disconnect the S7 back door opener switch assembly connector.
    2. Disconnect the E124 certification ECU (smart key ECU assembly) connector.
    3. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      S7-1 (L) - E124-13 (TSW6) Always Below 1 Ω
      S7-2 (E) - Body ground Always Below 1 Ω
      S7-1 (L) or E124-13 (TSW6) - Body ground Always 10 kΩ or higher

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  4

  4. INSPECT BACK DOOR OPENER SWITCH ASSEMBLY (LOCK SWITCH) 
    1. Remove the back door opener switch assembly (Refer to REMOVAL [08/2015 - ] ).
    2. Inspect the back door opener switch assembly (Refer to INSPECTION [08/2015 - 08/2017] ).

    Result: 

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 

    (Refer to REMOVAL [08/2015 - ] )

    Result: 

    NG 

    REPLACE BACK DOOR OPENER SWITCH ASSEMBLY 

    (Refer to REMOVAL [08/2015 - ] )