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Home >> Lexus >> 2007 >> IS 350 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (2GR-FSE) - System And Circuit Testing, On-Vehicle Inspection, Removal, Inspection And Installation >> ECM Power Source Circuit >> Inspection Procedure
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Inspection Procedure

  1. INSPECT ECM (+B, +B1 VOLTAGE) 
    1. Turn the engine switch on (IG).
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      VOLTAGE SPECIFIED CONDITION

      Tester Connection Specified Condition
      +B (A5-6) - E1 (E4-7) 9 to 14 V
      +B1 (A5-5) - E1 (E4-7) 9 to 14 V
      Fig 1: Identifying E4 And A5 ECM Connector
      G05316159Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

    NG: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND) 
    1. Disconnect the E4 ECM connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for open) 

      TESTER CONNECTION AND SPECIFIED CONDITION

      Tester Connection Specified Condition
      E1 (E4-7) - Body ground Below 1 Ω
      Fig 2: Identifying Harness And Connector (ECM - Body Ground)
      G05316160Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Reconnect the ECM connector.

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  3. INSPECT ECM (IGSW VOLTAGE) 
    1. Turn the engine switch on (IG).
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      VOLTAGE SPECIFIED CONDITION

      Tester Connection Specified Condition
      IGSW (A5-17) - E1 (E4-7) 9 to 14 V
      Fig 3: Identifying ECM (IGSW Voltage)
      G05316161Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to step  6

    NG: Go to next step 

  4. CHECK FUSE (IGN FUSE) 
    1. Remove the IGN fuse from the cowl side junction block RH.
    2. Measure the resistance of the IGN fuse.

      Standard resistance: 

      Below 1 Ω 

    3. Reinstall the IGN fuse.

    NG: REPLACE IGN FUSE 

    Fig 4: Identifying IGN Fuse
    G05285288Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  5. INSPECT IGNITION RELAY NO. 2 
    1. Remove the IG2 relay from the engine room J/B and R/B No. 2.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFIED CONDITION

      Tester Connection Specified Condition
      3-5 10 kΩ or higher
      3-5 Below 1 Ω (when battery voltage applied to terminals 1 and 2)
      Fig 5: Identifying Ignition Relay No. 2
      G04967794Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE IGNITION RELAY NO. 2 

    OK: GO TO  SMART ACCESS SYSTEM WITH PUSH-BUTTON START 

  6. INSPECT ECM (MREL VOLTAGE) 
    1. Turn the engine switch on (IG).
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      VOLTAGE SPECIFIED CONDITION

      Tester Connection Specified Condition
      MREL (A5-13) - E1 (E4-7) 9 to 14 V
      Fig 6: Identifying ECM (MREL Voltage)
      G05316164Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE ECM 

    OK: Go to next step 

  7. CHECK FUSE (EFI FUSE) 
    1. Remove the EFI fuse from the engine room No.2 junction block.
    2. Measure the resistance of the EFI fuse.
      Fig 7: Identifying EFI Fuse
      G05316165Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard resistance: 

      Below 1 Ω 

    3. Reinstall the EFI fuse.

    NG: REPLACE EFI FUSE 

    OK: Go to next step 

  8. INSPECT INTEGRATION RELAY (EFI MAIN RELAY) 
    1. Remove the integration relay from the engine room J/B and R/B No. 2.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFIED CONDITION

      Tester Connection Specified Condition
      2C-1 - 2A-8 10 kΩ or higher
      Below 1 Ω (when battery voltage applied to terminals 2A-6 and 2A-7)
      Fig 8: Identifying Integration Relay (EFI Main Relay)
      G05316166Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE INTEGRATION RELAY 

    OK: Go to next step 

  9. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY - ECM, INTEGRATION RELAY - BODY GROUND) 
    1. Check the harness and the connectors between the integration relay and the ECM.
      1. Remove the integration relay from the engine room J/B and R/B No. 2.
      2. Disconnect the A5 ECM connector.
      3. Measure the resistance according to the value(s) in the table below.

        Standard resistance (Check for open) 

        TESTER CONNECTION AND SPECIFIED CONDITION

        Tester Connection Specified Condition
        2A-6 - MREL (A5-13) Below 1 Ω

        Standard resistance (Check for short) 

        TESTER CONNECTION AND SPECIFIED CONDITION

        Tester Connection Specified Condition
        2A-6 or MREL (A5-13) - Body ground 10 kΩ or higher
        Fig 9: Identifying Harness And Connector (Integration Relay - ECM, Integration Relay - Body Ground)
        G05316167Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check the harness and the connectors between the integration relay and body ground.
      1. Remove the integration relay from the engine room J/B and R/B No. 2.
      2. Measure the resistance according to the value(s) in the table below.

        Standard resistance (Check for open) 

        TESTER CONNECTION AND SPECIFIED CONDITION

        Tester Connection Specified condition
        2A-7 - Body ground Below 1 Ω

    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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