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Section 355 (Ignition Switch & Key Unlock Warning System): Inspection

WARNING: This page is about a different car, the 2004 Lexus GS 430 and 2004 Lexus GS 300. However, it is still accessible from the selected car via links, so may be relevant.
  1. INSPECT IGNITION SWITCH CONTINUITY 
    INSPECTING 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: Replacing Switch
    G03471009Courtesy 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.

    Fig 2: Connecting Switch Connector
    G03471010Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    INSPECTING IGNITION CIRCUIT

    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
    G03471011Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  5. INSPECT KEY UNLOCK WARNING SWITCH CONTINUITY 
    INSPECT 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: Replacing Switch
    G03471012Courtesy 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.

    Fig 5: Connecting Switch Connector
    G03471013Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    INSPECT KEY UNLOCK WARNING SWITCH CIRCUIT

    Tester connection Condition Specified condition
    1 - Ground Constant Continuity

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