2004 Lexus SC 430FACTORY OEM SERVICE PROCEDURE

Inspection Procedure

  1. CHECK DTC OUTPUT 
    1. Check that the DTC B1221 is output when power window master switch is operated.

      HINT:

      • If B1221 is output when the switch is not operated, it is detected the switch sticking.
      • If B1221 is not output when switch is operated, it is detected that the switch contact condition is bad.
    1. NG: GO TO (See  FLOW CHART  ) 
    2. OK: Go to next step. 
  2. READ VALUE OF HAND-HELD TESTER 
    1. Check the power window master switch condition by the data monitor.

      Standard: (Driver door ECU) 

      Fig 1: Power Window Master Switch Operation Table (Drive Door ECU)
      G01449871Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. OK: Go to step   5 
    2. NG: Go to next step. 
  3. CHECK POWER WINDOW REGULATOR MASTER SWITCH ASSY 
    1. Remove the power window master switch.
    2. Check the continuity between the terminals when the power window switch for driver door is operated.
      Fig 2: Power Window Switch Continuity Table
      G01449872Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard: 

      Fig 3: Power Window Master Switch Connector Terminal Identification
      G01449873Courtesy 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 MASTER SWITCH - ECU) 
    1. Disconnect the master switch and D17 ECU connectors.
      Fig 4: Identifying Power Window Regulator Master Switch & Multiplex Network Door ECU (Front LH) Connector Terminals
      G01449874Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check the continuity between the connector terminals of master switch and ECU.

      Standard: 

      Fig 5: Power Window Master Switch Continuity Table
      G01449875Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 
    2. OK: Go to next step. 

    REPLACE MULTIPLEX NETWORK DOOR ECU FRONT LH 

  5. PERFORM ACTIVE TEST BY HAND-HELD TESTER 
    1. Check the power window operation by the active test.

      Standard: (Driver) 

      Fig 6: Driver Hand Held Tester Operation Table
      G01449876Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. OK: REPLACE MULTIPLEX NETWORK DOOR ECU FRONT LH 
    2. NG: Go to next step. 
  6. CHECK POWER WINDOW REGULATOR MOTOR ASSY LH 
    NOTE:
    • Be sure not to apply the battery voltage to terminal 2, 5 and 6 of the power window regulator motor assembly LH connector, because it might damage the pulse sensor and the limit switch. 
    • Be sure to reset the power window regulator motor assembly (Initial position setting of the limit switch) when the power window regulator motor assembly LH is Installed to the regulator. 
    • Work must be done with the power window regulator and door glass installed to the vehicle. 
    1. Check that the motor operates smoothly when the battery voltage is applied to each terminal of the connector.

      Standard: 

      Fig 7: Power Window Regulator Motor Testing Table
      G01449877Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Factory Service Tools

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.

Shop Manual-Ready ToolsCompare Repair QuoteQuote Shield Pro

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.