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Home >> Toyota >> 2011 >> RAV4 Base, 2.5 F, AWD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (2AR-FE) (Diagnostic Codes (P0455-P2A00) & Circuit Tests)) >> SFI System >> Circuit Tests >> ECM Power Source Circuit >> Procedure
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ECM Power Source Circuit: Procedure

  1. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY - BATTERY) 
    1. Remove the integration relay from the engine room No. 1 relay block.
      Fig 1: Identifying Integration Relay
      GTY218571Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the integration relay connector.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      Engine room relay block (1C-1) - Body ground Always 11 to 14 V
    4. Reinstall the integration relay.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (INTEGRATION RELAY - BATTERY) 

    OK: Go to next step 

  2. INSPECT INTEGRATION NO. 1 RELAY (EFI MAIN RELAY) 
    1. Inspect the EFI MAIN relay. Refer to ON-VEHICLE INSPECTION - Step 2 .

    NG → REPLACE INTEGRATION NO. 1 RELAY 

    OK: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY - ECM, BODY GROUND) 
    Fig 2: Checking Harness And Connector (Integration Relay - ECM, Body Ground)
    GTY237818Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Check the harness and connectors between the integration relay and ECM.
      1. Remove the integration relay from the engine room No. 1 relay block.
      2. Disconnect the ECM connector.
      3. Measure the resistance according to the value(s) in the table below.

        Standard Resistance (Check for open)

        Tester Connection Condition Specified Condition
        A9-6 (MREL) - 1A-2 Always Below 1 Ω
        A9-2 (+B) - 1A-4 Always
        A9-1 (+B2) - 1A-4 Always

        Standard Resistance (Check for short)

        Tester Connection Condition Specified Condition
        A9-6 (MREL) or 1A-2 - Body ground Always 10 kΩ or higher
        A9-2 (+B) or 1A-4 - Body ground Always
        A9-1 (+B2) or 1A-4 - Body ground Always
    2. Check the harness and connectors between the integration relay and body ground.
      1. Measure the resistance according to the value(s) in the table below.

        Standard Resistance (Check for open)

        Tester Connection Condition Specified Condition
        1A-3 - Body ground Always Below 1 Ω
    3. Reinstall the integration relay.
    4. Reconnect the ECM connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  4. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND) 
    1. Disconnect the ECM connector.
      Fig 3: Checking Harness And Connector (ECM - Body Ground)
      GTY236266Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for open)

      Tester Connection Condition Specified Condition
      B30-104 (E1) - Body ground Always Below 1 Ω
    3. Reconnect the ECM connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  5. INSPECT ECM (IGSW VOLTAGE) 
    1. Disconnect the ECM connectors.
      Fig 4: Inspecting ECM (IGSW Voltage)
      GTY226062Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Turn the ignition switch to ON.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      A9-28 (IGSW) - B30-104 (E1) Ignition switch ON 11 to 14 V
    4. Reconnect the ECM connectors.

    OK → See step   12 

    NG: Go to next step 

  6. INSPECT RELAY (IG2 RELAY POWER SOURCE) 
    Fig 5: Inspecting Relay (IG2 Relay Power Source)
    GTY234963Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the IG2 relay from the engine room No. 1 relay block.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      IG2 relay (3) - Body ground Always 11 to 14 V

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (IG2 RELAY - BATTERY) 

    OK: Go to next step 

  7. INSPECT IG2 RELAY 
    Fig 6: Identifying IG2 Relay Terminals
    GTY102844Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the IG2 relay from the engine room No. 1 relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      3 - 5 Battery voltage not applied to terminal 1 and 2 10 kΩ or higher
      3 - 5 Battery voltage applied to terminal 1 and 2 Below 1 Ω
    3. Reinstall the relay.

    NG → REPLACE IG2 RELAY 

    OK: Go to next step 

  8. CHECK HARNESS AND CONNECTOR (ECM - ENGINE ROOM NO. 1 RELAY BLOCK) 
    Fig 7: Checking Harness And Connector (ECM - Engine Room No. 1 Relay Block)
    GTY233261Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the IG2 relay from the engine room No. 1 relay block.
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for open)

      Tester Connection Condition Specified Condition
      IG2 relay (5) - A9-28 (IGSW) Always Below 1 Ω

      Standard Resistance (Check for short)

      Tester Connection Condition Specified Condition
      IG2 relay (5) or A9-28 (IGSW) - Body ground Always 10 kΩ or higher
    4. Reinstall the IG2 relay.
    5. Reconnect the ECM connector.

      Result

      Result Proceed to
      Out of normal range A
      Within normal range (w/ Smart Key System) B
      Within normal range (w/o Smart Key System) C

    B → See step   9 

    C → See step   10 

    A → REPAIR OR REPLACE HARNESS OR CONNECTOR 

  9. CHECK HARNESS AND CONNECTOR (ENGINE ROOM NO. 1 RELAY BLOCK - MAIN BODY ECU) 
    Fig 8: Checking Harness And Connector (Engine Room No. 1 Relay Block - Main Body ECU)
    GTY237458Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the IG2 relay from the engine room No. 1 relay block.
    2. Remove the instrument panel junction block (main body ECU).
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for open)

      Tester Connection Condition Specified Condition
      IG2 relay (1) - E16-5 (IG2D) Always Below 1 Ω
      IG2 relay (2) - Body ground Always Below 1 Ω

      Standard Resistance (Check for short)

      Tester Connection Condition Specified Condition
      IG2 relay (1) - E16-5 (IG2D) - Body ground Always 10 kΩ or higher
    4. Reinstall the IG2 relay.
    5. Reconnect the main body ECU.

    OK → See step   13 

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

  10. CHECK HARNESS AND CONNECTOR (ENGINE ROOM NO. 1 RELAY BLOCK - IGNITION SWITCH) 
    Fig 9: Checking Harness And Connector (Engine Room No. 1 Relay Block - Ignition Switch)
    GTY237459Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the IG2 relay from the engine room No. 1 relay block.
    2. Disconnect the ignition switch connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for open)

      Tester Connection Condition Specified Condition
      IG2 relay (1) - E3-6 (IG2) Always Below 1 Ω
      IG2 relay (2) - Body ground Always Below 1 Ω

      Standard Resistance (Check for short)

      Tester Connection Condition Specified Condition
      IG2 relay (1) or E3-6 (IG2) - Body ground Always 10 kΩ or higher
    4. Reinstall the IG2 relay.
    5. Reconnect the ignition switch connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  11. INSPECT IGNITION SWITCH ASSEMBLY 
    1. Inspect the ignition switch assembly. Refer to INSPECTION - Step 1 .

    NG → See step   14 

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

  12. REPLACE ECM. Refer to  REMOVAL 
  13. CHECK SMART KEY SYSTEM. Refer to  Power Source Mode does not Change 
  14. REPLACE IGNITION SWITCH ASSEMBLY. Refer to  REMOVAL 
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