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Home >> Lexus >> 2003 >> LS 430 >> Repair and Diagnosis >> External Pages >> Different car >> Section 424 (Power Door Lock Control System - Diagnostics) >> Power Door Lock Control System >> Key Lock-In Prevention Function Does Not Work Properly (Manual Operation And Operation Interlocked With Key Are Active) >> Inspection Procedure
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Inspection Procedure

WARNING: This page is about a different car, the 2003 Toyota 4Runner. However, it is still accessible from the selected car via links, so may be relevant.
  1. Read Value Of Hand-Held Tester 
    1. Using the hand-held tester, check that the unlock warning switch signal is output when the switch is operated.
      STANDARD (BODY ECU (SWITCH CONDITION)

      Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
      KEY UNLK WRN SW Key unlock warning SW signal/ON or OFF ON: Key is in ignition key cylinder OFF: Key is not in ignition key cylinder .....
    1. OK: Go to step   4 
    2. NG: Go to Next Step 
  2. Inspect Unlock Warning Switch Assy. 
    1. Remove the unlock warning switch.
    2. Inspect the unlock warning switch continuity.
      Fig 1: Inspecting Unlock Warning Switch Assy.
      G02815591Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Fig 2: Unlock Warning Switch Specifications Table
      G02815590Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: Replace Unlock Warning Switch Assy. 
    2. OK: Go to Next Step 
  3. Check Wire Harness (Unlock Warning Switch Assy. To Driver Side Junction Block Assy. (Body ECU) 
    1. Disconnect the K3 unlock warning switch and B12 body ECU connectors.
    2. Check the continuity between the terminals of the unlock warning switch (K3) and body ECU (B6) connectors.
      Fig 3: Checking K3 & B6 Connector Continuity
      G02815593Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Fig 4: Standard (Check For Open)
      G02815592Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: Repair Or Replace Harness And Connector 
    2. OK: Replace Instrument Panel Junction Block Assy. 
  4. Read Value Of Hand-Held Tester 
    1. Using the hand-held tester, check that the driver door courtesy switch signal is output when the switch is operated.
      STANDARD BODY ECU (SWITCH CONDITION)

      Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
      D DOR CTY SW Driver door courtesy SW signal/ON or OFF ON: Driver door is open OFF: Driver door is closed .....
    1. OK: Replace Courtesy Lamp Switch 
    2. NG: Go to Next Step 
  5. Inspect Courtesy Lamp Switch 
    1. Remove the courtesy lamp switch.
    2. Inspect the courtesy lamp switch continuity.
      Fig 5: Inspecting Courtesy Lamp Switch
      G02815595Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Fig 6: Courtesy Lamp Switch Specifications Table
      G02815594Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: Repair Or Replace Harness And Connector 
    2. OK: Go to Next Step 
  6. Check Wire Harness 
    1. Disconnect the courtesy lamp switch and body ECU connectors.
    2. Check the continuity between the terminals of the courtesy lamp switch (D12) and body ECU (B5) connectors.
      Fig 7: Identifying Courtesy Lamp Switch & ECU Connector Terminals
      G02815597Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Fig 8: Continuity Specifications Table
      G02815596Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: Repair Or Replace Harness And Connector 
    2. OK: Replace Instrument Panel Junction Block Assy. 
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