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Ignition Switch & Key Unlock Warning Switch: Inspection

  1. INSPECT IGNITION SWITCH CONTINUITY 
    SWITCH SPECIFICATION

    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
    Fig 1: Inspecting Ignition Switch Continuity
    G03375402Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    If continuity is not as specified, replace the switch.

  2. INSPECT IGNITION SWITCH CIRCUIT 

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

    Fig 2: Inspecting Ignition Switch Circuit
    G03375403Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    SWITCH SPECIFICATION

    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 IGNITION KEY ILLUMINATION OPERATION 

    Connect the battery positive (+) lead to terminal 2 and the battery negative (-) lead to terminal 6, and check that the indicator light comes on.

    If operation is not as specified, replace the switch.

  4. INSPECT IGNITION KEY ILLUMINATION CIRCUIT (See  PROBLEM SYMPTOMS TABLE  ) 
    Fig 3: Inspecting Ignition Key Illumination Circuit
    G03375404Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  5. INSPECT KEY UNLOCK WARNING SWITCH CONTINUITY 
    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.

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

    Fig 4: Connecting Switch Connector
    G03375405Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  6. INSPECT KEY UNLOCK WARNING SWITCH CIRCUIT 

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

    Fig 5: Identifying Wire Harness
    G03375406Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    CONTINUITY

    Tester connection Condition Specified condition
    2 - Ground Always Continuity

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