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Home >> Toyota >> 2007 >> Sequoia SR5, 4WD >> Repair and Diagnosis >> Engine Performance >> Engine Control System (2UZ-FE) >> SFI System >> ECM Power Source Circuit >> Inspection Procedure
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Inspection Procedure

  1. CHECK ECM (+B VOLTAGE) 
    1. Turn the ignition switch ON.
    2. Measure the voltage of the ECM connectors.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      +B (E4-1) - E1 (E6-1) 9 to 14 V

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

    Fig 1: Identifying E4 And E6 ECM Connector
    G05190604Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: GO TO next step 

  2. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND) 
    1. Disconnect the E6 ECM connector.
    2. Measure the resistance of the wire harness side connector.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      E1 (E6-1) - Body ground Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 2: Disconnecting E6 ECM Connector
    G04968171Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: GO TO next step 

  3. CHECK ECM (IGSW VOLTAGE) 
    1. Turn the ignition switch ON.
    2. Measure the voltage of the ECM connectors.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      IGSW(E4-9) - E1 (E6-1) 9 to 14 V

    OK:  GO TO step  6

    Fig 3: Identifying E4 And E6 ECM Connector
    G05190606Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: GO TO next step 

  4. INSPECT FUSE (IGN1) 
    1. Remove the IGN1 fuse from the instrument panel junction block RH.
    2. Measure the resistance of the IGN1 fuse.

      Standard resistance: 

      Below 1 Ω 

    NG: CHECK FOR SHORT IN ALL HARNESSES AND COMPONENTS CONNECTED TO IGN1 FUSE, AND REPLACE IGN1 FUSE 

    Fig 4: Identifying IGN1 Fuse From Instrument Panel Junction Block RH
    G05190607Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: GO TO next step 

  5. INSPECT IGNITION SWITCH ASSEMBLY 
    1. Remove the lower finish panel.
    2. Disconnect the I18 ignition switch connector.
    3. Measure the resistance of the ignition switch.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Switch position Tester Connection Specified Condition
      LOCK Always 10 kΩ or higher
      ACC 1-3 Below 1 Ω
      ON 1-2-3
      5-6
      START 1-2
      4-5-6
    4. Reconnect the ignition switch connector.

    NG: REPLACE IGNITION SWITCH ASSEMBLY 

    Fig 5: Identifying I18 Ignition Switch Connector
    G05190608Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - IGNITION SWITCH, IGNITION SWITCH - ECM) 

  6. CHECK ECM (MREL VOLTAGE) 
    1. Turn the ignition switch ON.
    2. Measure the voltage of the ECM connectors.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      MREL(E4-8) - E1 (E6-1) 9 to 14 V

    NG: REPLACE ECM 

    Fig 6: Identifying E4 And E6 ECM Connector
    G05190609Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: GO TO next step 

  7. INSPECT FUSE (EFI NO. 1) 
    1. Remove the EFI NO. 1 fuse from the engine room junction block.
    2. Measure the resistance of the EFI NO. 1 fuse.

      Standard resistance: 

      Below 1 Ω 

    NG: CHECK FOR SHORT IN ALL HARNESSES AND COMPONENTS CONNECTED TO EFI NO. 1 FUSE, AND REPLACE EFI FUSE 

    Fig 7: Identifying EFI No. 1 Fuse From Engine Room Junction Block
    G05190610Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: GO TO next step 

  8. INSPECT EFI RELAY (Marking: EFI OR ECD) 
    1. Remove the EFI relay from the engine room junction block.
    2. Measure the resistance of the EFI relay.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Terminal Connection Specified Condition
      3 - 5 10 kΩ or higher
      3 - 5 Below 1 Ω. (when battery voltage is applied to terminals 1 and 2)

    NG: REPLACE EFI RELAY 

    Fig 8: Inspecting A/F Relay
    G04967794Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: GO TO next step 

  9. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND) 
    1. Disconnect the E4 ECM connector.
    2. Measure the resistance between the wire harness side connector and body ground.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      MREL (E4-8) - Body ground Below 1 Ω
    3. Reconnect the ECM connector.

    OK: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 9: Disconnecting E4 ECM Connector
    G05190612Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: CHECK FOR INTERMITTENT PROBLEMS