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Home >> Lexus >> 2002 >> SC 430 >> Repair and Diagnosis >> Body & Frame >> Windows >> Power Window Control System - Diagnosis >> Window Cannot Be Operated Via Regulator Switch In Driver's Side (Power Window Master Switch Circuit) >> Inspection Procedure
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Inspection Procedure

  1. USE LEXUS HAND-HELD TESTER 
    1. NO: GO TO STEP   4 
    2. YES: GO TO NEXT STEP 
  2. READ VALUE OF LEXUS HAND-HELD TESTER (DRIVER'S DOOR ECU) 
    1. Monitor Code:
      1. Inspect the monitor code of the door ECU.
    NOTE:
    • Monitor code shows the switch condition when a DTC is output.
    • In case of that a code is indicated when the switch is not operated, it is detected that the switch is stuck.

      In case of that a code is not indicated when the switch is operated, it is detected that the switch contact condition is bad.

    DIAGNOSIS CHART

    SAE code Item Diagnosis Specified condition
    B1221 Driver's side master switch ON Master switch (remote switch for other seats) Neutral --> UP or DOWN No code --> Yes
    1. NG: GO TO STEP   4 
    2. OK: GO TO NEXT STEP 
  3. READ VALUE OF LEXUS HAND-HELD TESTER(DRIVER'S DOOR ECU) 
    1. Data Monitor:
      1. Perform a data monitor of the door ECU.

      Standard: 

      Door ECU (driver's side) (switch condition) 

      SWITCH OPERATION

      Switch operation Measuring condition Specified condition
      P/W AUTO SW pressed - unpressed ON / OFF
    1. OK: GO TO FLOW CHART (See  WINDOW CANNOT BE OPERATED VIA REGULATOR SWITCH IN DRIVER'S SIDE (POWER WINDOW MOTOR CIRCUIT)  ) 
    2. NG: GO TO NEXT STEP 
  4. INSPECT POWER WINDOW REGULATOR MASTER SWITCH ASSY 
    1. Continuity check of the power window switch
      1. Check the continuity of each terminal of the connector, when each switch is operated.
    NOTE:
    • Mark "<-->" means that continuity exists
    • Mark "-->" means that approximately 4 kΩ diode exists.

    Standard: 

    STANDARD CHART

    Switch operation Tester connection (Passenger's window)
    UP AUTO 6 <=> 20 <=> 16
    UP MANUAL 6 <=> 20
    OFF -
    DOWN MANUAL 6 <=> 11
    DOWN AUTO 6 <=> 11 <=> 16
    Fig 1: Checking Continuity Of Terminal Of Connector
    G03386859Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPLACE POWER WINDOW REGULATOR MASTER SWITCH ASSY 
    2. OK: GO TO NEXT STEP 
  5. CHECK WIRE HARNESS 
    1. Check the continuity of the wire harness between the power window master switch and the driver door ECU.
      1. Disconnect the power window master switch connector and the driver door ECU connector D17.
    2. Check the continuity of the vehicle's side wire harness between the master switch and the driver door ECU.
    Fig 2: Disconnecting Power Window Master Switch Connector & Driver Door ECU Connector D17
    G03386860Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    TERMINAL SPECIFICATION

    Terminal No. (master switch <=> driver door ECU) Specified condition
    6 (PW) <=> D17-21 (PWS) Continuity
    10 (E) <=> D17-29 (PWE) Continuity
    16 (AUTO) <=> D17-2 (AUTO) Continuity
    20 (DUP) <=> D17-23 (MUP) Continuity
    11 (DDN) <=> D17-25 (MUN) Continuity
    NOTE:
    • With LEXUS hand-held tester, proceed to "OK-A"
    • Without LEXUS hand-held tester, proceed to "OK-B"
    1. OK-A: REPLACE MULTIPLEX NETWORK DOOR ECU FRONT LH 
    2. OK-B: GO TO FLOW CHART (See  WINDOW CANNOT BE OPERATED VIA REGULATOR SWITCH IN DRIVER'S SIDE (POWER WINDOW MOTOR CIRCUIT)  ) 
    3. NG: REPAIR OR REPLACE WIRE HARNESS OR CONNECTOR 
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