2005 Lexus SC 430FACTORY OEM SERVICE PROCEDURE

Inspection Procedure

  1. CHECK MANUAL UP/DOWN FUNCTION 
    1. Check that the manual UP/DOWN function using the master switch and regulator switch can operate all the power windows.

      OK: Manual UP/DOWN function operates normally. 

    1. NG: OTHER PROBLEM (See  POWER WINDOW DOES NOT OPERATE ON PASSENGER SIDE  
    2. OK: Go to next step. 
  2. READ DATA LIST (PASSENGER SWITCH ON MASTER SWITCH) 
    1. Check the DATA LIST for proper functioning of the power window switch on the master switch.

      Multiplex network door ECU front LH: 

      Fig 1: Multiplex Network Door ECU Front LH Table
      G02956647Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: ON (power window regulator switch on master switch operates) appears on screen. 

    1. NG: Go to step   3 
    2. OK: REPLACE MULTIPLEX NETWORK DOOR ECU FRONT LH 
  3. INSPECT POWER WINDOW REGULATOR MASTER SWITCH ASSY 
    1. Remove the master switch.
    2. Measure the resistance of the switch when the switch is operated.

      Standard: 

      Passenger switch 

      POWER WINDOW REGULATOR MASTER SWITCH ASSY (PASSENGER SWITCH)

      Switch Condition Tester Connection Specified Condition
      AUTO UP 3 (DT1) - 14 (SC2) Below 1 ohms
      3 (DT1) - 15 (SC3)
      UP 3 (DT1) - 14 (SC2) Below 1 ohms
      OFF - -
      DOWN 3 (DT1) - 13 (SC1) Below 1 ohms
      AUTO DOWN 3 (DT1) - 13 (SC1) Below 1 ohms
      3 (DT1) - 15 (SC3)

      Window lock switch 

      POWER WINDOW REGULATOR MASTER SWITCH ASSY (WINDOW LOCK SWITCH)

      Switch Condition Tester Condition Specified Condition
      UNLOCK 7 (W/L) - 6 (PW) Below 1 ohms
      LOCK 7 (W/L) - 6 (PW) 10 k ohms or higher
      Fig 2: Inspecting Power Window Regulator Master Switch Assy
      G02956648Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPLACE POWER WINDOW REGULATOR MASTER SWITCH ASSY 
    2. OK: Go to next step. 
  4. CHECK WIRE HARNESS (POWER WINDOW REGULATOR MASTER SWITCH ASSY - MULTIPLEX NETWORK DOOR ECU FRONT LH) 
    1. Disconnect the P14 switch connector.
    2. Disconnect the D17 ECU connector.
    3. Measure the resistance of the wire harness side connectors.

      Standard: 

      POWER WINDOW REGULATOR MASTER SWITCH ASSY - MULTIPLEX NETWORK DOOR ECU FRONT LH

      Tester Connection Specified Condition
      P14-6 (PW) - D17-21 (PWS) Below 1 ohms
      P14-7 (W/L) - D17-9 (WLSW) Below 1 ohms
      P14-3 (DT1) - D17-5 (DT1) Below 1 ohms
      P14-13 (SC1) - D17-16 (SC1) Below 1 ohms
      P14-14 (SC2) - D17-15 (SC2) Below 1 ohms
      P14-15 (SC3) - D17-14 (SC3) Below 1 ohms
      P14-6 (PW) or D17-21 (PWS) - Body ground 10 k ohms or higher
      P14-7 (W/L) or D17-9 (WLSW) - Body ground 10 k ohms or higher
      P14-3 (DT1) or D17-5 (DT1) - Body ground 10 k ohms or higher
      P14-13 (SC1) or D17-16 (SC1) - Body ground 10 k ohms or higher
      P14-14 (SC2) or D17-15 (SC2) - Body ground 10 k ohms or higher
      P14-15 (SC3) or D17-14 (SC3) - Body ground 10 k ohms or higher
      Fig 3: Checking Wire Harness (Power Window Regulator Master Switch Assy - Multiplex Network Door ECU Front LH
      G02956649Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 
    2. OK: Go to next step. 
  5. CHECK WIRE HARNESS (MULTIPLEX NETWORK DOOR ECU FRONT LH - MULTIPLEX NETWORK DOOR ECU FRONT RH) 
    1. Disconnect the D17 ECU connector.
    2. Disconnect the P9 ECU connector.
    3. Measure the resistance of the wire harness side connectors.

      Standard: 

      MULTIPLEX NETWORK DOOR ECU FRONT LH - MULTIPLEX NETWORK DOOR ECU FRONT RH

      Tester Connection Specified Condition
      D17-20 (WLS1) - P9-9 (WLSW) Below 1 ohms
      D17-20 (WLS1) or P9-9 (WLSW) - Body ground 10 k ohms or higher
      Fig 4: Checking Wire Harness (Multiplex Network Door ECU Front LH - Multiplex Network Door ECU Front RH)
      G02956650Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 
    2. OK: Go to next step. 
  6. CHECK OPERATION OF 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 the remote UP/DOWN function operates normally.

      OK: Remote UP/DOWN function operates normally. 

    1. NG: REPLACE MULTIPLEX NETWORK DOOR ECU FRONT RH 
    2. OK: END 
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