2003 Lexus SC 430FACTORY OEM SERVICE PROCEDURE

Section 532 (Power Door Lock Control System): Inspection

WARNING: This page is about a different car, the 2004 Lexus LX 470. However, it is still accessible from the selected car via links, so may be relevant.
  1. Master swatch: 

    INSPECT DRIVER'S DOOR LOCK CONTROL SWITCH CONTINUITY 

    TESTER CONNECTION SPECIFICATION

    Switch position Tester connection Specified condition
    LOCK 3 - 4 Continuity
    OFF - No continuity
    UNLOCK 3 - 14 Continuity
    Fig 1: Inspecting Driver'S Door Lock Control Switch Connector
    G03485910Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    If continuity is not as specified, replace the switch.

  2. INSPECT PASSENGER'S DOOR LOCK CONTROL SWITCH CONTINUITY 
    TESTER CONNECTION SPECIFICATION

    Switch position Tester connection Specified condition
    LOCK 3 - 2 Continuity
    OFF - No continuity
    UNLOCK 1 - 2 Continuity

    If continuity is not as specified, replace the switch.

    Fig 2: Inspecting Passenger'S Door Lock Control Switch Connector
    G03485911Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. INSPECT DOOR KEY LOCK AND UNLOCK SWITCH CONTINUITY 
    TESTER CONNECTION SPECIFICATION

    Switch position Tester connection Specified condition
    LOCK 1 - 2 Continuity
    OFF - No continuity
    UNLOCK 1 - 3 Continuity

    If continuity is not as specified, replace the switch.

    Fig 3: Inspecting Door Key Lock And Unlock Switch Connector
    G03485912Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. Front door: 

    INSPECT DOOR UNLOCK DETECTION SWITCH CONTINUITY 

    TESTER CONNECTION SPECIFICATION

    Switch position Tester connection Specified condition
    OFF (Door Lock set to LOCK) - No continuity
    ON (Door Lock set to UNLOCK) 1 - 4 Continuity

    If continuity is not as specified, replace the switch.

    Fig 4: Inspecting Door Unlock Detection Switch Connector
    G03485913Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  5. Rear door: 

    INSPECT DOOR UNLOCK DETECTION SWITCH CONTINUITY 

    TESTER CONNECTION SPECIFICATION

    Switch position Tester connection Specified condition
    OFF (Door Lock set to LOCK) - No continuity
    ON (Door Lock set to UNLOCK) 1 - 4 Continuity

    If continuity is not as specified, replace the switch.

    Fig 5: Inspecting Door Unlock Detection Switch Connector
    G03485914Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  6. Back door: 

    INSPECT DOOR UNLOCK DETECTION SWITCH CONTINUITY 

    TESTER CONNECTION SPECIFICATION

    Switch position Tester connection Specified condition
    OFF (Door Lock set to LOCK) - No continuity
    ON (Door Lock set to UNLOCK) 1 - 4 Continuity

    If continuity is not as specified, replace the switch.

    Fig 6: Inspecting Door Unlock Detection Switch Connector
    G03485915Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  7. Back door: 

    INSPECT DOOR UNLOCK DETECTION SWITCH CIRCUIT (See  PATTERN SELECT SWITCH CIRCUIT (PWR MODE SWITCH)  ) 

  8. Front door: 

    INSPECT DOOR LOCK MOTOR OPERATION 

    1. Connect the battery positive (+) lead to terminal 3 and the battery negative (-) lead to terminal 2, and check that the door lock link moves to UNLOCK position.
      Fig 7: Inspecting Door Lock Motor Connector
      G03485916Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Reverse the polarity and check that the door lock link moves to LOCK position.

      If operation is not as specified, replace the door lock assembly.

      Fig 8: Checking Door Lock Link Moves Lock Position
      G03485917Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  9. Rear door: 

    INSPECT DOOR LOCK MOTOR OPERATION 

    1. Connect the battery positive (+) lead to terminal 3 and the battery negative (-) lead to terminal 2, and check that the door lock link moves to UNLOCK position.
      Fig 9: Inspecting Door Lock Motor Connector
      G03485918Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Reverse the polarity and check that the door lock link moves to LOCK position.

      If operation is not as specified, replace the door lock assembly.

      Fig 10: Checking Door Lock Link Moves To Lock Position
      G03485919Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  10. Backdoor: 

    INSPECT DOOR LOCK MOTOR OPERATION 

    1. Connect the battery positive (+) lead to terminal 3 and the battery negative (-) lead to terminal 2, and check that the door lock link moves to UNLOCK position.
      Fig 11: Inspecting Door Lock Motor Connector
      G03485920Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Reverse the polarity and check that the door lock link moves to LOCK position.

      If operation is not as specified, replace the door lock assembly.

  11. Backdoor: 

    INSPECT DOOR LOCK MOTOR CIRCUIT 

    (See  PROBLEM SYMPTOMS TABLE  ) 

    Fig 12: Inspecting Door Lock Motor Circuit Connector
    G03485921Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  12. Front door: 

    INSPECT PTC THERMISTOR OPERATION (Using an ammeter) 

    1. Connect the battery negative (-) lead to terminal 2.
    2. Connect the ammeter positive (+) lead to terminal 3 and the ammeter negative (-) lead to the battery negative (-) terminal, and check that the current changes from approximately 3.2 A to less than 0.5 A within 20 to 70 seconds.
      Fig 13: Inspecting PTC Thermistor Operation
      G03485922Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Disconnect the leads from terminals.
    4. Approximately 60 seconds later, connect the battery positive (+) lead to terminal 2 and the battery negative (-) lead to terminal 3, and check that the door lock moves to the LOCK position.

      If operation is not as specified, replace the door lock assembly

      Fig 14: Disconnecting Leads From Terminals
      G03485923Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  13. Rear door: 

    INSPECT PTC THERMISTOR OPERATION (Using an ammeter) 

    1. Connect the battery negative (-) lead to terminal 2.
    2. Connect the ammeter positive (+) lead to terminal 3 and the ammeter negative (-) lead to battery negative (-) terminal, and check that the current changes from approximately 3.2 A to less than 0.5 A within 20 to 70 seconds.
      Fig 15: Inspecting PTC Thermistor Connector
      G03485924Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Disconnect the leads from terminals.
    4. Approximately 60 seconds later, connect the battery positive (+) lead to terminal 2 and the battery negative (-) lead to terminal 3, and check that the door lock moves to the LOCK position.

      If operation is not as specified, replace the door lock assembly.

      Fig 16: Disconnecting Leads From Terminals
      G03485925Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  14. Backdoor: 

    INSPECT PTC THERMISTOR OPERATION (Using an ammeter) 

    1. Connect the battery negative (-) lead to terminal 2.
    2. Connect the ammeter positive (+) lead to terminal 3 and the ammeter negative (-) lead to battery negative (-) terminal, and check that the current changes from approximately 3.2 A to less than 0.5 A within 20 to 70 seconds.
      Fig 17: Inspecting PTC Thermistor Connector
      G03485926Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Disconnect the leads from terminals.
    4. Approximately 60 seconds later, connect the battery positive (+) lead to terminal 2 and the battery negative (-) lead to terminal 3, and check that the door lock moves to the LOCK position.

      If operation is not as specified, replace the door lock assembly.

      Fig 18: Disconnecting Leads From Terminals
      G03485927Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  15. Front door: 

    INSPECT PTC THERMISTOR OPERATION (Using an ammeter with a current-measuring probe) 

    1. Connect the battery positive (+) lead to terminal 3 and the battery negative (-) lead to terminal 2.
    2. Attach a current-measuring probe to either the positive (+) lead or the negative (-) lead, and check that the current changes from approximately 3.2 A to less than 0.5 A within 20 to 70 seconds.
      Fig 19: Connecting Battery Positive (+) Lead To Terminal 3 And Battery Negative (-) Lead To Terminal 2
      G03485928Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Disconnect the leads from terminals.
    4. Approximately 60 seconds later, reverse the polarity, and check that the door lock moves to the LOCK position.

      If operation is not as specified, replace the door lock assembly.

      Fig 20: Disconnecting Leads From Terminals
      G03485929Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  16. Rear door: 

    INSPECT PTC THERMISTOR OPERATION (Using an ammeter with a current-measuring probe) 

    1. Connect the battery positive (+) lead to terminal 3 and the battery negative (-) lead to terminal 2.
    2. Attach a current-measuring probe to either the positive (+) lead or the negative (-) lead, and check that the current changes from approximately 3.2 A to less than 0.5 A within 20 to 70 seconds.
      Fig 21: Connecting Battery Positive (+) Lead To Terminal And Battery Negative (-) Lead To Terminal
      G03485930Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Disconnect the leads from terminals.
    4. Approximately 60 seconds later, reverse the polarity, and check that the door lock moves to the LOCK position.

      If operation is not as specified, replace the door lock assembly.

      Fig 22: Checking Door Lock Moves To Lock Position
      G03485931Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  17. Backdoor: 

    INSPECT PTC THERMISTOR OPERATION (Using an ammeter with a current-measuring probe) 

    1. Connect the battery positive (+) lead to terminal 3 and the battery negative (-) lead to terminal 2.
    2. Attach a current-measuring probe to either the positive (+) lead or the negative (-) lead, and check that the current changes from approximately 3.2 A to less than 0.5 A within 20 to 70 seconds.
      Fig 23: Checking Current Changes From Approximately
      G03485932Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Disconnect the leads from terminals.
    4. Approximately 60 seconds later, reverse the polarity, and check that the door lock moves to the LOCK position.

      If operation is not as specified, replace the door lock assembly.

      Fig 24: Disconnecting Leads From Terminals
      G03485933Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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