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Home >> Lexus >> 2007 >> GS 350 AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (2GR-FSE) - System And Circuit Testing, On-Vehicle Inspection, Removal, Inspection, 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 SPECIFICATION

      Tester Connection Specified Condition
      A6-6 (+B) - E7-7 (E1) 9 to 14 V
      A6-5 (+B1) - E7-7 (E1) 9 to 14 V
    Fig 1: Identifying ECM Connector Terminals
    G05285285Courtesy 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 E7 ECM connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for open) 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      E7-7 (E1) - Body ground Below 1 Ω
    Fig 2: Disconnecting E7 ECM Connector
    G05285286Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR 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 SPECIFICATION

      Tester Connection Specified Condition
      A6-17 (IGSW) - E7-7 (E1) 9 to 14 V
    Fig 3: Identifying ECM Connector Terminals
    G05285287Courtesy 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 

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

    NG: CHECK FOR SHORT IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE 

    OK: Go to next step 

  5. INSPECT IG2 RELAY 
    1. Remove the IG2 relay from the engine room No. 2 relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFICATION

      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 IG2 Relay Connector Terminals
    G04967794Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE IG2 RELAY 

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

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

    Standard voltage 

    VOLTAGE SPECIFICATION

    Tester Connection Specified Condition
    A6-13 (MREL) - E7-7 (E1) 9 to 14 V
    Fig 6: Identifying ECM Connector Terminals
    G05285290Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE ECM 

    OK: Go to next step 

  9. 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.

      Standard resistance: 

      Below 1 Ω 

    Fig 7: Identifying EFI Fuse
    G05285291Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: CHECK FOR SHORT IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE 

    OK: Go to next step 

  10. INSPECT INTEGRATION RELAY (EFI MAIN RELAY) 
    1. Remove the integration relay from the engine room No. 2 junction block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFICATION

      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 Connector Terminals
    G05285292Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE INTEGRATION RELAY 

    OK: Go to next step 

  11. 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 No. 2 junction block.
      2. Disconnect the A6 ECM connector.
      3. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for open) 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      2A-6 - A6-13 (MREL) Below 1 Ω

      Standard resistance (Check for short) 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      2A-6 or A6-13 (MREL) - Body ground 10 kΩ or higher
    2. Check the harness and the connectors between the integration relay and body ground.
      1. Remove the integration relay from the engine room No. 2 junction block.
      2. Measure the resistance according to the value(s) in the table below.

        Standard resistance (Check for open) 

        RESISTANCE SPECIFICATION

        Tester Connection Specified condition
        2A-7 - Body ground Below 1 Ω
    Fig 9: Disconnecting A6 ECM Connector
    G05285293Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

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

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