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Home >> Toyota >> 2009 >> Sienna XLE, FWD >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System - System & Component Testing, On-Vehicle Inspection, Removal, Inspection & Installation >> ECM Power Source Circuit >> Inspection Procedure
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Inspection Procedure

  1. INSPECT ECM (+B VOLTAGE) 
    1. Turn the ignition switch to the ON position.
    2. Measure the voltage according to the value (s) in the table below.

      Standard voltage 

      VOLTAGE SPECIFICATIONS

      Tester Connection Specified Condition
      +B (E4-1) - E1 (E11-1) 9 to 14 V
      Fig 1: Identifying E11 And E4 ECM Connector Terminal
      G05136277Courtesy 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 E11 ECM connector.
      2. Fig 2: Identifying E11 ECM Connector Terminal
      G05136278Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value (s) in the table below.

      Standard resistance: Check for open 

      RESISTANCE SPECIFIED CONDITIONS

      Tester Connection Specified Condition
      E1 (E11-1) - Body ground Below 1 Ω
    3. Reconnect the ECM connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (ECM - BODY GROUND) 

    OK: Go to next step. 

  3. INSPECT ECM (IGSW VOLTAGE) 
    1. Turn the ignition switch to the ON position.
    2. Measure the voltage according to the value (s) in the table below.

      Standard voltage 

      VOLTAGE SPECIFICATIONS

      Tester Connection Specified Condition
      IGSW (E4-9) - E1 (E11-1) 9 to 14 V
      Fig 3: Identifying E11 And E4 ECM Connector Terminal
      G05136279Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK:  Go to step  8

    NG: Go to next step. 

  4. CHECK FUSE (IGN FUSE) 
    1. Remove the IGN fuse from the driver side junction block.
      2. Fig 4: Identifying Driver Side Junction Block
      G05136280Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the IGN fuse resistance.

      Standard resistance: Below 1 Ω 

    3. Reinstall the IGN fuse.

    NG: REPLACE FUSE (IGN FUSE) 

    OK: Go to next step. 

  5. CHECK HARNESS AND CONNECTOR (IGNITION SWITCH - ECM) 
    1. Disconnect the E4 ECM connector.
    2. Disconnect the I15 ignition switch connector.
      3. Fig 5: Identifying I15 Ignition Switch Connector
      G05136281Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value (s) in the table below.

      Standard resistance: Check for open 

      RESISTANCE SPECIFIED CONDITIONS

      Tester Connection Specified Condition
      IG2 (I15-6) - IGSW (E4-9) Below 1 Ω

      Check for short 

      RESISTANCE SPECIFIED CONDITIONS

      Tester Connection Specified Condition
      IG2 (I15-6) or IGSW (E4-9) - Body ground 10 kΩ or higher
    4. Reconnect the ECM connector.
    5. Reconnect the ignition switch connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (IGNITION SWITCH - ECM) 

    OK: Go to next step. 

  6. INSPECT IGNITION SWITCH ASSEMBLY 
    1. Inspect the ignition or starter switch assembly (See REMOVAL ).

    NG: REPLACE IGNITION SWITCH ASSEMBLY  (See REMOVAL )

    OK: Go to next step. 

  7. CHECK FUSE (AM2 FUSE) 
    1. Remove the AM2 fuse from the engine room junction block.
      2. Fig 6: Identifying Engine Room Junction Block
      G05136282Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value (s) in the table below.

      Standard resistance: Below 1 Ω 

    3. Reinstall the AM2 fuse.

    NG: REPLACE FUSE (AM2 FUSE) 

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

  8. INSPECT ECM (MREL VOLTAGE) 
    1. Turn the ignition switch to the ON position.
    2. Measure the voltage according to the value (s) in the table below.

      Standard voltage 

      VOLTAGE SPECIFICATIONS

      Tester Connection Specified Condition
      MREL (E4-8) - E1 (E11-1) 9 to 14 V
      Fig 7: Identifying E11 And E4 Connector Terminal
      G05136283Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE ECM  (See REMOVAL  )

    OK: Go to next step. 

  9. CHECK FUSE (EFI NO. 1 FUSE) 
    1. Remove the EFI No. 1 fuse from the engine room junction block.
      2. Fig 8: Identifying Engine Room Junction Block
      G05136135Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the EFI No. 1 fuse resistance.

      Standard resistance: Below 1 Ω 

    3. Reinstall the EFI No. 1 fuse.

    NG: REPLACE FUSE (EFI NO. 1 FUSE) 

    OK: Go to next step. 

  10. INSPECT RELAY (EFI RELAY) 
    1. Remove the EFI relay from the engine room junction block.
    2. Measure the EFI relay resistance.

      Standard resistance 

      RESISTANCE SPECIFIED CONDITIONS

      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 9: Identifying Relay Circuit With Terminal
      G04942983Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Reinstall the EFI relay.

    NG: REPLACE RELAY (EFI RELAY) 

    OK: Go to next step. 

  11. CHECK HARNESS AND CONNECTOR (EFI RELAY - ECM) 
    1. Check the harness and connector between the EFI relay and ECM.
      1. Remove the EFI relay from the engine room junction block.
        2. Fig 10: Identifying Engine Room Junction Block And ECM Connector
        G05136286Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Disconnect the E4 ECM connector.
      3. Measure the resistance according to the value (s) in the table below.

        Standard resistance: Check for open 

        RESISTANCE SPECIFIED CONDITIONS

        Tester Connection Specified Condition
        EFI relay terminal (2) - MREL (E4-8) Below 1 Ω

        Check for short 

        RESISTANCE SPECIFIED CONDITIONS

        Tester Connection Specified Condition
        EFI relay terminal (2) or MREL (E4-8) - Body ground 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (EFI RELAY - ECM) 

    OK: Go to next step. 

  12. CHECK HARNESS AND CONNECTOR (EFI RELAY - ECM) 
    1. Remove the EFI relay from the engine room junction block.
      2. Fig 11: Identifying Engine Room Junction Block And ECM Connector
      G05136287Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the E4 ECM connector.
    3. Measure the resistance according to the value (s) in the table below.

      Standard resistance: Check for open 

      RESISTANCE SPECIFIED CONDITIONS

      Tester Connection Specified Condition
      EFI relay terminal (3) - +B (E4-1) Below 1 Ω
      EFI relay terminal (3) - +B2 (E4-2) Below 1 Ω

      Check for short 

      RESISTANCE SPECIFIED CONDITIONS

      Tester Connection Specified Condition
      EFI relay terminal (3) or +B (E4-1) - Body ground 10 kΩ or higher
      EFI relay terminal (3) or +B2 (E4-2) - Body ground 10 kΩ or higher
    4. Reinstall the EFI relay.
    5. Reconnect the ECM connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (EFI RELAY - ECM) 

    OK: Go to next step. 

  13. CHECK HARNESS AND CONNECTOR (EFI RELAY - BODY GROUND) 
    1. Check the harness and connector between the EFI relay and body ground.
      1. Measure the resistance according to the value (s) in the table below.

        Standard resistance: Check for open 

        RESISTANCE SPECIFIED CONDITIONS

        Tester Connection Specified Condition
        EFI relay terminal (1) - Body ground Below 1 Ω
        Fig 12: Identifying Engine Room Junction Block And EFI Relay
        G05136288Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Reinstall the EFI relay.
      3. Reconnect the ECM connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (EFI RELAY - BODY GROUND) 

    OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (EFI RELAY - BATTERY) 

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