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Inspection Procedure

WARNING: This page is about a different car, the 2008 Toyota Yaris. However, it is still accessible from the selected car via links, so may be relevant.
  1. INSPECT FUSE (ECU-B) 
    1. Remove the ECU-B fuse from the engine room R/B and J/B.
      2. Fig 1: Identifying Fuse (ECU-B)
      G04830963Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the ECU-B fuse resistance.

      Standard resistance: Below 1 Ω 

    3. Reinstall the ECU-B fuse.

    NG: REPLACE FUSE 

    OK: Go to next step. 

  2. INSPECT FUSE (IGN) 
    1. Remove the IGN fuse from the main body ECU.
      2. Fig 2: Identifying Fuse (IGN)
      G05591761Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the IGN fuse resistance.

      Standard resistance: Below 1 Ω 

    3. Reinstall the IGN fuse.

    NG: REPLACE FUSE 

    OK: Go to next step. 

  3. INSPECT INTEGRATION RELAY (IG2 RELAY AND AM2 FUSE) 
    1. Remove the integration relay from the engine room R/B and J/B.
    2. Inspect the AM2 fuse.
      1. Remove the AM2 fuse from the integration relay.
      2. Measure the resistance of the AM2 fuse.

        Standard resistance: Below 1 Ω 

      3. Reinstall the AM2 fuse.
    3. Inspect the IG2 relay.
      1. Measure the resistance between the terminals shown below.

        Standard resistance 

        TESTER CONNECTION SPECIFIED CONDITION

        Tester Connections Specified Conditions
        1C-1-1B-4 10 kΩ or higher
        Below 1 Ω (when battery voltage is applied to terminals 1B-2 and 1B-3)
        1C-1-1B-1 Below 1 Ω
        Fig 3: Identifying Integration Relay (IG2 Relay And AM2 Fuse)
        G04830965Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Reinstall the integration relay.

    NG: REPLACE INTEGRATION RELAY 

    OK: Go to next step. 

  4. INSPECT IGNITION SWITCH ASSEMBLY 
    1. Disconnect the D8 ignition switch connector.
      2. Fig 4: Identifying Ignition Switch Assembly Connector
      G04828333Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance between the terminals shown below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Key Position Tester Connection Specified Condition
      LOCK - 10 kΩ or higher
      ACC 2-4 Below 1 Ω
      ON 1-2-4 Below 1 Ω
      5-6 Below 1 Ω
      START 1-3-4 Below 1 Ω
      5-6-7 Below 1 Ω
    3. Reconnect the D8 ignition switch connector.

    NG: REPLACE IGNITION SWITCH ASSEMBLY 

    OK: Go to next step. 

  5. CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU - BATTERY AND BODY GROUND) 
    1. Disconnect the D23 transponder key ECU connector.
    2. Measure the voltage of the wire harness side connector.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      D23-1 (+B) - Body ground Always 11 to 14 V
      D23-2 (IG) - Body ground Ignition switch OFF Below 1 V
      Ignition switch ON 11 to 14 V
    3. Measure the resistance of the wire harness side connector.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      D23-16 (GND) - Body ground Below 1 Ω
    4. Reconnect the D23 transponder key ECU connector.
      Fig 5: Identifying Transponder Key ECU Connector Terminals
      G04830967Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE TRANSPONDER KEY ECU ASSEMBLY 

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