Back Power Window Auto Up / Down Function does not Operate [12/2024 - ]: Procedure

2025 Toyota 4Runner SR5, 4WDSECTION Procedure
  1. PERFORM INITIALIZATION (AUTO UP / DOWN FUNCTION) 
    1. Initialize the power window regulator motor assembly RH (for back door).

      Refer to REGISTRATION [12/2024 - ]

    2. Check that the back door power window moves when the auto up and down functions of the back door power window regulator switch on the map light assembly are operated.

      Refer to OPERATION CHECK [12/2024 - ]

      OK

      Back door auto up and down functions are normal.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END (PROBLEM DUE TO INITIALIZATION FAILURE) 

    Result: 

    NG 

    See step  2

  2. CHECK POWER WINDOW REGULATOR MOTOR ASSEMBLY RH (for Back Door) 
    1. Disconnect the K2 main body ECU (multiplex network body ECU) connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      K2-4 (AUT2) - Body ground Ignition switch ON 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) 

    Refer to REMOVAL [12/2024 - ]

    Result: 

    NG 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (POWER WINDOW REGULATOR MOTOR ASSEMBLY RH (for Back Door) - MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)) 
    1. Disconnect the b7 power window regulator motor assembly RH (for back door) connector.
    2. Disconnect the K2 main body ECU (multiplex network body ECU) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      b7-4 (AUTO) - K2-4 (AUT2) Always Below 1 Ω
      b7-4 (AUTO) or K2-4 (AUT2) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE POWER WINDOW REGULATOR MOTOR ASSEMBLY RH (for Back Door) 

    Refer to REMOVAL [12/2024 - ]

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.