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Ignition Switch & Key Unlock Warning System: Inspection

  1. INSPECT IGNITION SWITCH CONTINUITY 
    SWITCH POSITION TESTER CONNECTION AND CONDITION DESCRIPTION

    Switch position Tester connection Specified condition
    LOCK - No continuity
    ACC 2-3 Continuity
    ON 2-3-4 6-7 Continuity
    START 1-2-4 6-7-8 Continuity

    If continuity is not as specified, replace the switch.

    Fig 1: Inspecting Ignition Switch Continuity
    G03494179Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. INSPECT IGNITION SWITCH CIRCUIT 

    Connect the switch connector and inspect the connector on wire harness side from the back side, as shown in Fig 2 .

    Fig 2: Inspecting Ignition Switch Circuit
    G03494180Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    TESTER CONNECTION AND SPECIFIED CONDITION

    Tester connection Condition Specified condition
    2 - Ground Always Battery Positive Voltage
    3 - Ground Ignition switch ACC or ON Battery Positive Voltage
    4 - Ground Ignition switch ON Battery Positive Voltage
    6 - Ground Ignition switch ON or START Battery Positive Voltage
    7 - Ground Always Battery Positive Voltage
    8 - Ground Ignition switch START Battery Positive Voltage

    If circuit is not as specified, inspect the circuits connected to other parts.

  3. INSPECT KEY UNLOCK WARNING SWITCH CONTINUITY 
    SWITCH POSITION TESTER CONNECTION AND CONDITION DESCRIPTION

    Switch position Tester connection Specified condition
    OFF (Key removed) 1-2 No continuity
    ON (Key set) 1-2 Continuity

    If continuity is not as specified, replace the switch.

    Fig 3: Inspecting Key Unlock Warning Switch Continuity
    G03494181Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. INSPECT KEY UNLOCK WARNING SWITCH CIRCUIT (See  KEY UNLOCK WARNING SWITCH CIRCUIT  ) 

    Connect the switch connector and inspect the connector on wire harness side from the back side, as shown in Fig 4 .

    Fig 4: Inspecting Key Unlock Warning Switch Circuit
    G03494182Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    TESTER CONNECTION AND SPECIFIED CONDITION

    Tester connection Condition Specified condition
    1 - Ground Always Continuity

    If circuit is not as specified, inspect the circuits connected to other parts.