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Inspection Procedure

  1. CHECK ECM (+B VOLTAGE) 
    1. Turn the power switch ON (IG).
    2. Measure the voltage between the specified terminals of the E5 and E7 ECM connectors.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      E7-4 (+B) - E5-28 (E1) 9 to 14 V

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON PROBLEM SYMPTOMS TABLE 

    Fig 1: Identifying E5 And E7 ECM Connectors Terminals
    G05188959Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to next step. 

  2. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND) 
    1. Disconnect the E5 ECM connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for open) 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      E5-28 (E1) - Body ground Below 1 Ω
    3. Reconnect the ECM connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 2: Identifying E5 ECM Connector
    G05188960Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step. 

  3. CHECK ECM (IGSW VOLTAGE) 
    1. Turn the power switch ON (IG).
    2. Measure the voltage between the specified terminals of the E5 and E6 ECM connectors.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      E6-9 (IGSW) - E5-28 (E1) 9 to 14 V

    OK:  Go to step  7

    Fig 3: Identifying E5 And E6 ECM Connectors
    G05188961Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to next step. 

  4. INSPECT FUSE (IGN FUSE) 
    1. Remove the IGN fuse from the driver side junction block.
    2. Measure the resistance of the IGN fuse.

      Standard resistance: 

      Below 1 Ω 

    3. Reinstall the IGN fuse.

    NG: CHECK FOR SHORT IN ALL HARNESS AND COMPONENTS CONNECTED TO FUSE 

    Fig 4: Identifying Driver Side Junction Block
    G05188962Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step. 

  5. INSPECT INTEGRATION RELAY (IG2 RELAY) 
    1. Remove the integration relay from the engine room relay block.
    2. Inspect the IG2 relay.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      3K-1 - 3I-4 10 kΩ or higher
      3K-1 - 3I-4 Below 1 Ω. (Apply battery voltage to terminals 3I-2 and 3I-3)
    3. Reinstall the integration relay.

    NG: REPLACE INTEGRATION RELAY 

    Fig 5: Identifying Integration Relay And Connector Terminal
    G05188963Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step. 

  6. INSPECT FUSE (AM2 FUSE) 
    1. Remove the AM2 fuse from the engine room relay block.
    2. Measure the resistance of the AM2 fuse.

      Standard resistance: 

      Below 1 Ω 

    3. Reinstall the AM2 fuse.

    NG: CHECK FOR SHORT IN ALL HARNESS AND COMPONENTS CONNECTED TO FUSE 

    Fig 6: Identifying AM2 Fuse And Engine Room Relay Block
    G05188964Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: CHECK AND REPAIR HARNESS AND CONNECTOR (BATTERY - IG2 RELAY, IG2 RELAY - ECM) 

  7. CHECK ECM (MREL VOLTAGE) 
    1. Turn the power switch ON (IG).
    2. Measure the voltage between the specified terminals of the E5 and E7 ECM connectors.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      E7-7 (MREL) - E5-28 (E1) 9 to 14 V

    NG: REPLACE ECM 

    Fig 7: Identifying E5 And E7 ECM Connectors
    G05188965Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step. 

  8. INSPECT FUSE (EFI FUSE) 
    1. Remove the EFI fuse from the engine room relay block.
    2. Measure the resistance of the EFI fuse.

      Standard resistance: 

      Below 1 Ω 

    3. Reinstall the EFI fuse.

    NG: CHECK FOR SHORT IN ALL HARNESS AND COMPONENTS CONNECTED TO FUSE 

    Fig 8: Identifying Engine Room Relay Block And EFI Fuse
    G05188851Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step. 

  9. INSPECT INTEGRATION RELAY (EFI M RELAY) 
    1. Remove the integration relay from the engine room relay block.
    2. Inspect the EFI M relay.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      3K-1 - 3I-8 10 kΩ or higher
      3K-1 - 3I-8 Below 1 Ω (Apply battery voltage to terminals 3I-6 and 3I-7)
    3. Reinstall the integration relay.

    NG: REPLACE INTEGRATION RELAY 

    Fig 9: Identifying Integration Relay And Connector Terminal
    G05188690Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step. 

  10. CHECK HARNESS AND CONNECTOR (EFI M RELAY - ECM, EFI M RELAY - BODY GROUND) 
    1. Check the harness and connectors between the EFI M relay and ECM connector.
      1. Remove the integration relay from the engine room relay block.
        Fig 10: Identifying Engine Room Relay Block
        G05188968Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Disconnect the E7 ECM connector.
      3. Measure the resistance according to the value(s) in the table below.

        Standard resistance (Check for open) 

        TESTER CONNECTION SPECIFIED CONDITION

        Tester Connection Specified Condition
        3I-6 (EFI M relay) - E7-7 (MREL) Below 1 Ω

        Standard resistance (Check for short) 

        TESTER CONNECTION SPECIFIED CONDITION

        Tester Connection Specified Condition
        3I-6 (EFI M relay) or E7-7 (MREL) - Body ground 10 kΩ or higher
        Fig 11: Identifying E7 ECM Connector Terminal
        G05188969Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      4. Reinstall the integration relay.
      5. Reconnect the ECM connector.
    2. Check the harness and the connectors between the EFI M relay and the body ground.
      1. Remove the integration relay from the engine room relay block.
      2. Measure the resistance between the wire harness side connector and body ground.

        Standard resistance (Check for open) 

        TESTER CONNECTION SPECIFIED CONDITION

        Tester Connection Specified Condition
        3I-7 (EFI M relay) - Body ground Below 1 Ω
      3. Reinstall the integration relay.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: CHECK AND REPAIR HARNESS AND CONNECTOR (TERMINAL +B OF ECM - BATTERY POSITIVE TERMINAL) 

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