LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2021 >> LC 500 2D Convertible >> Repair and Diagnosis >> Body & Frame >> Windows >> Power Window Control System - Diagnostic Codes & Symptom Tests (Convertible) >> Power Window Control System >> DTC B2312: Power Window Switch Malfunction [07/2020 - ] >> Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC B2312: Power Window Switch Malfunction [07/2020 - ]: Procedure

  1. CHECK FOR DTC 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [07/2020 - ]

      Body Electrical > Master Switch > Clear DTCs 

      Body Electrical > D-Door Motor > Clear DTCs 

      Body Electrical > P-Door Motor > Clear DTCs 

    2. Check for DTCs.

      Refer to DTC CHECK / CLEAR [07/2020 - ]

      Body Electrical > Master Switch > Trouble Codes 

      Body Electrical > D-Door Motor > Trouble Codes 

      Body Electrical > P-Door Motor > Trouble Codes 

      OK

      DTC B2312 is not output.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END (DUE TO SWITCH BEING OPERATED FOR 20 SECONDS OR MORE) 

    Result: 

    NG 

    See step  2

  2. CHECK FOR DTC 
    1. Check the parts which the DTCs have been output from.

      Result

      Result Proceed to
      DTC output from Master Switch A
      DTC output from D-Door Motor B
      DTC output from P-Door Motor C

    Result: 

    A 

    REPLACE MULTIPLEX NETWORK MASTER SWITCH ASSEMBLY. Refer to  REMOVAL [07/2020 - ] 

    Result: 

    C 

    See step  7

    Result: 

    B 

    See step  3

  3. READ VALUE USING TECHSTREAM (D-DOOR MOTOR) 
    1. Read the Data List according to the display on the Techstream.

      Refer to DATA LIST / ACTIVE TEST [07/2020 - ]

      Body Electrical > D-Door Motor > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      D Door P/W Up SW Driver door power window manual up switch signal OFF or ON OFF: Driver door power window manual up switch not being operated
      ON: Driver door power window manual up switch being operated      		 -
      D Door P/W Down SW Driver door power window manual down switch signal OFF or ON OFF: Driver door power window manual down switch not being operated
      ON: Driver door power window manual down switch being operated      		 -

      Body Electrical > D-Door Motor > Data List 

      Tester Display
      D Door P/W Up SW
      D Door P/W Down SW

      OK

      On the Techstream screen, ON or OFF is displayed accordingly.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE POWER WINDOW REGULATOR MOTOR ASSEMBLY LH. Refer to  REMOVAL [07/2020 - 05/2023]  , or refer to  REMOVAL [05/2023 - ] 

    Result: 

    NG 

    See step  4

  4. CHECK MULTIPLEX NETWORK MASTER SWITCH ASSEMBLY 
    1. Disconnect the power window regulator motor assembly LH connector.
      GTY820726Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Power Window Regulator Motor Assembly LH)
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      S2-10 (UP) - Body ground Engine switch on (IG) 11 to 14 V
      S2-7 (DOWN) - Body ground Engine switch on (IG) 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE POWER WINDOW REGULATOR MOTOR ASSEMBLY LH. Refer to  REMOVAL [07/2020 - 05/2023]  , or refer to  REMOVAL [05/2023 - ] 

    Result: 

    NG 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (MULTIPLEX NETWORK MASTER SWITCH ASSEMBLY - POWER WINDOW REGULATOR MOTOR ASSEMBLY LH) 
    1. Disconnect the U2 multiplex network master switch assembly connector.
    2. Disconnect the S2 power window regulator motor assembly LH connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      U2-20 (UP) - Body ground Always 10 kΩ or higher
      U2-15 (DOWN) - Body ground Always 10 kΩ or higher
      S2-10 (UP) - Body ground Always 10 kΩ or higher
      S2-7 (DOWN) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE MULTIPLEX NETWORK MASTER SWITCH ASSEMBLY. Refer to  REMOVAL [07/2020 - ] 

    Result: 

    NG 

    See step  6

  6. INSPECT FRONT DOOR WIRE LH 
    1. Turn the engine switch off.
      GTY799647Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 Front Door Wire LH - -
      *a Front view of wire harness connector
      (to Multiplex Network Master Switch Assembly Side Connector)      		 *b Front view of wire harness connector
      (to Vehicle Side Connector)
    2. Disconnect the U2 front door wire LH connector.
    3. Disconnect the US1 front door wire LH connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      U2-20 (UP) - Body ground Always 10 kΩ or higher
      U2-15 (DOWN) - Body ground Always 10 kΩ or higher
      US1-5 - Body ground Always 10 kΩ or higher
      US1-13 - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    NG 

    REPLACE FRONT DOOR WIRE LH. Refer to  DISASSEMBLY [07/2020 - 05/2023]  , or refer to  DISASSEMBLY [05/2023 - ] 

  7. READ VALUE USING TECHSTREAM (P-DOOR MOTOR) 
    1. Read the Data List according to the display on the Techstream.

      Refer to DATA LIST / ACTIVE TEST [07/2020 - ]

      Body Electrical > P-Door Motor > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      P Door P/W Auto SW Front passenger door power window auto switch signal OFF or ON OFF: Front passenger door power window auto switch not being operated
      ON: Front passenger door power window auto switch being operated      		 -
      P Door P/W Up SW Front passenger door power window manual up switch signal OFF or ON OFF: Front passenger door power window manual up switch not being operated
      ON: Front passenger door power window manual up switch being operated      		 -
      P Door P/W Down SW Front passenger door power window manual down switch signal OFF or ON OFF: Front passenger door power window manual down switch not being operated
      ON: Front passenger door power window manual down switch being operated      		 -

      Body Electrical > P-Door Motor > Data List 

      Tester Display
      P Door P/W Auto SW
      P Door P/W Up SW
      P Door P/W Down SW

      OK

      On the Techstream screen, ON or OFF is displayed accordingly.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE POWER WINDOW REGULATOR MOTOR ASSEMBLY RH. Refer to  REMOVAL [07/2020 - 05/2023]  , or refer to  REMOVAL [05/2023 - ] 

    Result: 

    NG 

    See step  8

  8. INSPECT POWER WINDOW REGULATOR SWITCH ASSEMBLY 
    1. Remove the power window regulator switch assembly.

      Refer to REMOVAL [07/2020 - ]

    2. Inspect the power window regulator switch assembly.

      Refer to INSPECTION [07/2020 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE POWER WINDOW REGULATOR SWITCH ASSEMBLY. Refer to  REMOVAL [07/2020 - ] 

    Result: 

    OK 

    See step  9

  9. CHECK HARNESS AND CONNECTOR (POWER WINDOW REGULATOR SWITCH ASSEMBLY - POWER WINDOW REGULATOR MOTOR ASSEMBLY RH) 
    1. Disconnect the T1 power window regulator switch assembly connector.
    2. Disconnect the R2 power window regulator motor assembly RH connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      T1-2 (UP) - Body ground Always 10 kΩ or higher
      T1-4 (AUTO) - Body ground Always 10 kΩ or higher
      T1-10 (DOWN) - Body ground Always 10 kΩ or higher
      R2-10 (UP) - Body ground Always 10 kΩ or higher
      R2-4 (AUTO) - Body ground Always 10 kΩ or higher
      R2-7 (DOWN) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE POWER WINDOW REGULATOR MOTOR ASSEMBLY RH. Refer to  REMOVAL [07/2020 - 05/2023]  , or refer to  REMOVAL [05/2023 - ] 

    Result: 

    NG 

    See step  10

  10. INSPECT FRONT DOOR WIRE RH 
    1. Turn the engine switch off.
      GTY794232Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 Front Door Wire RH - -
      *a Front view of wire harness connector
      (to Vehicle Side Connector)      		 *b Front view of wire harness connector
      (to Power Window Regulator Switch Assembly Side Connector)
    2. Disconnect the T1 front door wire RH connector.
    3. Disconnect the TR1 front door wire RH connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      T1-2 (UP) - Body ground Always 10 kΩ or higher
      T1-10 (DOWN) - Body ground Always 10 kΩ or higher
      T1-4 (AUTO) - Body ground Always 10 kΩ or higher
      TR1-5 - Body ground Always 10 kΩ or higher
      TR1-13 - Body ground Always 10 kΩ or higher
      TR1-6 - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    NG 

    REPLACE FRONT DOOR WIRE RH. Refer to  DISASSEMBLY [07/2020 - 05/2023]  , or refer to  DISASSEMBLY [05/2023 - ] 

scientia non olet · About LEMON Manuals