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Home >> Toyota >> 2003 >> Tundra Base, Automatic >> Repair and Diagnosis >> Body & Frame >> Door Locks >> Vehicle Intrusion Protection System - Diagnostics >> Key Unlock Warning Switch Circuit >> Inspection Procedure
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Inspection Procedure

  1. Inspect key unlock warning switch. 

    CHECK: 

    Check the continuity between the terminals.

    Fig 1: Identifying Key Unlock Warning Switch And Connector Terminals
    G02843946Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: 

    SPECIFIED CONDITION

    Switch position Tester connection Specified condition
    Switch free (Key removed) 1 - 2 No continuity
    Switch pushed (Key inserted) 1 - 2 Continuity
    1. NG : Replace key unlock warning switch. 
    2. OK : Go to Next Step. 
  2. Check harness and connector between TVIP ECU and key unlock warning switch. 

    PREPARATION: 

    1. Disconnect the T12 TVIP ECU connector.
      Fig 2: Identifying T12 TVIP ECU And U1 Key Unlock Warning Switch Connectors
      G02843947Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the U1 key unlock warning switch connector.

    CHECK: 

    Check the continuity between the wire harness side connectors.

    OK 

    SPECIFIED CONDITION

    Symbols (Terminal No.) (TVIP ECU <--> Key Unlock Warning switch) Specified condition
    KSW (T12 - 6) <--> - (U1 - 2) Continuity
    1. NG : Repair or replace harness and connector. 
    2. OK : Go to Next Step. 
  3. Check harness and connector between key unlock warning switch and body around. 

    PREPARATION: 

    Disconnect the U1 key unlock warning switch connector.

    CHECK: 

    Check the continuity between the U1 key unlock warning switch wire harness side connector and body ground.

    Fig 3: Identifying U1 Key Unlock Warning Switch Connector
    G02843948Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: 

    SPECIFIED CONDITION

    Terminal No. Specified condition
    U1 - 1 <--> Body ground Continuity
    1. NG : Repair or replace harness and connector. 
    2. OK : Check and replace TVIP ECU.