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Home >> Toyota >> 2008 >> Avalon XLS >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System (2GR-FE) - System And Circuit Testing, On-Vehicle Inspection, Removal, Inspection, Installation >> ECM Power Source Circuit >> Inspection Procedure
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Inspection Procedure

  1. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND) 
    1. Disconnect the B50 ECM connector.
    2. Measure the resistance between the terminals.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      E1 (B50-81) - Body ground Below 1 Ω
    3. Reconnect the ECM connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 1: Identifying B50 ECM Connector
    G05404741Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  2. CHECK ENGINE ROOM JUNCTION BLOCK (EFI RELAY VOLTAGE) 
    1. Remove the EFI No. 1 fuse from the engine room R/B.
    2. Turn the ignition switch on (IG).
    3. Measure the voltage between the terminals.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      EFI No. 1 fuse (1) - Body ground 9 to 14 V

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (EFI NO. 1 FUSE - BATTERY) 

    Fig 2: Identifying EFI No. 1 Fuse From Engine Room R/B
    G05404742Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  3. INSPECT EFI NO. 1 FUSE 
    1. Remove the EFI No. 1 fuse from the engine room R/B.
    2. Measure the EFI No. 1 fuse resistance.

      Standard resistance: 

      Below 1 Ω 

    3. Reinstall the EFI No. 1 fuse.

    NG: REPLACE EFI NO. 1 FUSE 

    Fig 3: Identifying EFI No. 1 Fuse From Engine Room R/B
    G04996501Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  4. INSPECT ENGINE ROOM JUNCTION BLOCK (EFI RELAY) 
    1. Remove the engine room junction block from the engine room R/B.
    2. Measure the resistance between the terminals.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      1D-4 - 1D-6 10 kΩ or higher
      1D-4 - 1D-6 Below 1 Ω (Battery voltage applied between terminals 1H-10 and 1H-2)
    3. Reinstall the engine room junction block.

    NG: REPLACE ENGINE ROOM JUNCTION BLOCK 

    Fig 4: Identifying Engine Room Junction Block Terminal (EFI Relay)
    G05404744Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  5. CHECK HARNESS AND CONNECTOR (ECM - ENGINE ROOM JUNCTION BLOCK) 
    1. Disconnect the ECM connector.
    2. Remove the engine room junction block from the engine room R/B.
    3. Measure the resistance between the terminals.

      Standard resistance (Check for open) 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      1D-4 - +B (A55-2) Below 1 Ω
      1D-4 - +B2 (A55-1) Below 1 Ω

      Standard resistance (Check for short) 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      1D-4 or +B (A55-2) - Body ground 10 kΩ or higher
      1D-4 or +B2 (A55-1) - Body ground 10 kΩ or higher
    4. Reinstall the engine room junction block.
    5. Reconnect the ECM connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 5: Identifying ECM Connector
    G05404745Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  6. INSPECT ECM (IGSW VOLTAGE) 
    1. Disconnect the ECM connector.
    2. Measure the voltage between the terminals.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      IGSW (A55-28) - Body ground 9 to 14 V
    3. Reconnect the ECM connector.

    OK:  Go to step  10

    Fig 6: Identifying ECM Connector
    G04973803Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to next step 

  7. INSPECT IGNITION RELAY NO. 2 
    1. Remove the IG2 relay from the engine room R/B.
    2. Measure the resistance the terminals.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      3 - 5 10 kΩ or higher
      3 - 5 Below 1 Ω (Battery voltage applied between terminals 1 and 2)
    3. Reinstall the IG2 relay.

    NG: REPLACE IGNITION RELAY NO. 2 

    Fig 7: Inspecting Ignition Relay No. 2
    G04942976Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  8. CHECK HARNESS AND CONNECTOR (IG2 RELAY - BODY GROUND) 
    1. Remove the IG2 relay from the engine room R/B.
    2. Measure the resistance between the terminals.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      IG2 relay terminal 2 - Body ground Below 1 Ω
    3. Reinstall the IG2 relay.

    Result 

    RESULT CHART

    Result Proceed to
    OK (Without smart key system) A
    OK (With smart key system) B
    NG C

    B:  Go to SMART KEY SYSTEM

    C : REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 8: Identifying IG2 Relay From Engine Room R/B
    G05404748Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    A: Go to next step 

  9. INSPECT IGNITION SWITCH ASSEMBLY 
    1. Disconnect the ignition switch connector.
    2. Measure the resistance between the terminals.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Ignition Switch Position Specified Condition
      All terminals LOCK 10 kΩ or higher
      2 - 4 ACC Below 1 Ω
      1 - 2 - 4, 5 - 6 ON
      1 - 3 - 4, 5 - 6 - 7 START
    3. Reconnect the ignition switch connector.
      Fig 9: Identifying Ignition Switch Connector
      G04973181Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE IGNITION SWITCH ASSEMBLY 

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

  10. CHECK HARNESS AND CONNECTOR (ECM - EFI RELAY) 
    1. Disconnect the ECM connector.
    2. Remove the engine room junction block.
    3. Measure the resistance between the terminals.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      MREL (A55-44) - 1H-10 Below 1 Ω
    4. Reconnect the ECM connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 10: Identifying ECM Connector
    G05404750Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : REPLACE ECM  (See ECM  )

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