LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2006 >> SC 430 >> Repair and Diagnosis >> Body & Frame >> Windows >> Power Window Control System - Diagnostics >> DTC B1221: Power Window Switch Circuit On Driver Door >> Inspection Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Inspection Procedure

  1. 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: 

      Driver switch 

      POWER WINDOW REGULATOR MASTER SWITCH ASSY (DRIVER SWITCH)

      Switch Condition Tester Connection Specified Condition
      AUTO UP 6 (PW) - 16 (AUTO) Below 1 ohms
      AUTO UP 6 (PW) - 20 (DUP) Below 1 ohms
      UP 6 (PW) - 20 (DUP) Below 1 ohms
      OFF - -
      DOWN 6 (PW) - 11 (DDN) Below 1 ohms
      AUTO DOWN 6 (PW) - 11 (DDN) Below 1 ohms
      AUTO DOWN 6 (PW) - 16 (AUTO) Below 1 ohms

      Door control switch 

      POWER WINDOW REGULATOR MASTER SWITCH ASSY (DOOR CONTROL SWITCH)

      Switch Condition Tester Condition Specified Condition
      UNLOCK 10 (E) - 18 (MUL) Below 1 ohms
      LOCK 8 (ML) - 10 (E) Below 1 ohms
      OFF - -
      Fig 1: Identifying Power Window Regulator Master Switch Assy
      G02956618Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPLACE POWER WINDOW REGULATOR MASTER SWITCH ASSY 
    2. OK: Go to next step. 
  2. 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
      P14-10 (E) - D17-29 (PWE) Below 1 ohms
      P14-16 (AUTO) - D17-2 (AUTO) Below 1 ohms
      P14-20 (DUP) - D17-23 (MUP) Below 1 ohms
      P14-11 (DDN) - D17-25 (MDN) Below 1 ohms
      P14-8 (ML) - D17-8 (ML) Below 1 ohms
      P14-18 (MUL) - D17-19 (MUL) Below 1 ohms
      P14-6 (PW) or D17-21 (PWS) - Body ground 10 k ohms or higher
      P14-10 (E) or D17-29 (PWE) - Body ground 10 k ohms or higher
      P14-16 (AUTO) or D17-2 (AUTO) - Body ground 10 k ohms or higher
      P14-20 (DUP) or D17-23 (MUP) - Body ground 10 k ohms or higher
      P14-11 (DDN) or D17-25 (MDN) - Body ground 10 k ohms or higher
      P14-8 (ML) or D17-8 (ML) - Body ground 10 k ohms or higher
      P14-18 (MUL) or D17-19 (MUL) - Body ground 10 k ohms or higher
      Fig 2: Checking Wire Harness (Power Window Regulator Master Switch Assy - Multiplex Netowrk Door ECU Front LH)
      G02956619Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 
    2. OK: REPLACE MULTIPLEX NETWORK DOOR ECU FRONT LH 
scientia non olet · About LEMON Manuals