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Home >> Lexus >> 2007 >> SC 430 >> Repair and Diagnosis >> Body & Frame >> Windows >> Windshield/WINDOWGLASS >> Power Window Control System >> DTC B1231 Jam Protection Limit Switch Circuit on Driver Door; DTC B1232 Jam Protection Pulse Switch Circuit on Driver Door >> Inspection Procedure
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Inspection Procedure

  1. CHECK POWER WINDOW OPERATION 
    1. Lower the driver door power window from the fully closed position to the fully open position. Check if the DTC is erased.

      Result 

      RESULT REFERENCE CHART

      Result Proceed to
      DTC is not erased A
      DTC is erased B

      HINT:

      If the DTC is erased, it is possible that the multiplex network door ECU front LH incorrectly detected this DTC previously.

    B: END 

    A: Go to Next Step 

  2. RESET POWER WINDOW REGULATOR MOTOR 
    1. Reset the power window regulator motor (see INITIALIZATION  ).
    2. Check if the power window AUTO UP / DOWN function operates normally.

      OK: AUTO UP / DOWN function operates normally. 

    OK: END 

    NG: Go to Next Step 

  3. READ VALUE OF INTELLIGENT TESTER (LIMIT SWITCH) 
    1. Check the DATA LIST for proper functioning of the limit switch.

      Multiplex network door ECU front LH 

      ITEM MEASUREMENT NORMAL CONDITION CHART

      Item Measurement Item / Display (Range) Normal Condition Diagnostic Note
      LIMIT SW Jam protection limit switch / ON or OFF ON: Jam protection limit switch operates
      OFF: Jam protection limit switch does not operate
      -

      OK: ON (jam protection limit switch operates) appears on screen. 

    OK: REPLACE MULTIPLEX NETWORK DOOR ECU FRONT LH 

    NG: Go to Next Step 

  4. CHECK WIRE HARNESS (DOOR ECU FRONT LH - POWER WINDOW MOTOR LH) 
    1. Disconnect the D19 ECU connector.
    2. Disconnect the P15 motor connector.
      Fig 1: Identifying D19 And P15 Connector Terminals
      G05293431Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance 

      ITEM MEASUREMENT NORMAL CONDITION CHART

      Tester Connection Specified Condition
      D19-10 (LMT) - P15-4 (LMT) Below 1 Ω
      D19-21 (PLS) - P15-3 (PLS) Below 1 Ω
      D19-11 (SGND) - P15-5 (E) Below 1 Ω
      D19-10 (LMT) or P15-4 (LMT) - Body ground 10 kΩ or higher
      D19-21 (PLS) or P15-3 (PLS) - Body ground 10 kΩ or higher
      D19-11 (SGND) or P15-5 (E) - Body ground 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to Next Step 

  5. REPLACE MULTIPLEX NETWORK DOOR ECU FRONT LH 
    1. Temporarily replace the multiplex network door ECU front LH with a new or normally functioning one.
    2. Check that a DTC is not output.

      OK: DTC is not output. 

    NG: REPLACE FRONT POWER WINDOW REGULATOR MOTOR ASSEMBLY LH 

    OK: END (ECU DEFECTIVE)