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Ignition Switch & Key Unlock Warning System: Inspection

  1. INSPECT IGNITION SWITCH CONTINUITY 
    IGNITION SWITCH CONTINUITY

    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
    G03598679Courtesy 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
    G03598680Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    IGNITION SWITCH CIRCUIT SPECIFIED CONDITION

    Tester connection Condition Specified condition
    2 - Ground Constant 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 Constant 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 IGNITION KEY ILLUMINATION OPERATION 

    Connect the positive (+) lead from the battery to terminal 1 and the negative (-) lead to terminal 2, and check that the indicator light lights up.

    If operation is not as specified, replace the switch.

  4. INSPECT IGNITION KEY ILLUMINATION CIRCUIT 

    (See  ILLUMINATION CIRCUIT  ) 

    Fig 3: Inspecting Ignition Key Illumination Circuit
    G03598681Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  5. INSPECT KEY UNLOCK WARNING SWITCH CONTINUITY 
    KEY UNLOCK WARNING SWITCH CONTINUITY

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

    If continuity is not as specified, replace the switch.

    Fig 4: Inspecting Key Unlock Warning Switch Continuity
    G03598682Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  6. 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 5.

    Fig 5: Identifying Terminals Of Key Unlock Warning Switch Circuit Connector
    G03598683Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    KEY UNLOCK WARNING SWITCH CIRCUIT CONNECTOR SPECIFIED CONDITION

    Tester connection Condition Specified condition
    1 - Ground Constant Continuity

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