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Inspection Procedure

  1. INSPECT ECM (+B VOLTAGE) 
    1. Turn the ignition switch on (IG).
    2. Measure the voltage between the terminals of the A24 and B47 ECM connectors.

      Standard voltage 

      TESTER CONNECTIONS AND SPECIFIED CONDITIONS

      Tester Connections Specified Conditions
      +B (A24-1) - E1 (B47-1) 9 to 14 V
      Fig 1: Inspecting ECM (+B Voltage)
      G04375203Courtesy 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 B47 ECM connector.
    2. Measure the resistance between the terminal of the ECM connector and body ground.

      Standard resistance (Check for open) 

      TESTER CONNECTIONS AND SPECIFIED CONDITIONS

      Tester Connections Specified Conditions
      E1 (B47-1) - Body ground Below 1
    3. Reconnect the ECM connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 2: Disconnecting B47 ECM Connector
    G04375204Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step. 

  3. INSPECT ECM (IGSW VOLTAGE) 
    1. Turn the ignition switch on (IG).
    2. Measure the voltage between the terminals of the A24 and B47 ECM connectors.

      Standard voltage 

      TESTER CONNECTIONS AND SPECIFIED CONDITIONS

      Tester Connections Specified Conditions
      IGSW (A24-9) - E1 (B47-1) 9 to 14 V

    OK: Go to step   6 

    Fig 3: Inspecting ECM (IGSW Voltage)
    G04375205Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to next step. 

  4. CHECK FUSE (IGN FUSE) 
    1. Remove the IGN fuse from the instrument panel J/B.
    2. Measure the IGN fuse resistance.

      Standard resistance: Below 1  

    3. Reinstall the IGN fuse.

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

    Fig 4: Checking Fuse
    G04375206Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step. 

  5. INSPECT IGNITION OR STARTER SWITCH ASSEMBLY 
    1. Inspect the ignition or starter switch assembly (See INSPECTION ).

    NG: REPLACE IGNITION OR STARTER SWITCH ASSEMBLY 

    OK: Go to next step. 

  6. INSPECT ECM (MREL VOLTAGE) 
    1. Turn the ignition switch on (IG).
      Fig 5: Inspecting ECM (MREL Voltage)
      G04375207Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage between the terminals of the A24 and B47 ECM connectors.

      Standard voltage 

      TESTER CONNECTIONS AND SPECIFIED CONDITIONS

      Tester Connections Specified Conditions
      MREL (A24-8) - E1 (B47-1) 9 to 14 V

    NG: REPLACE ECM 

    OK: Go to next step. 

  7. CHECK FUSE (EFI FUSE) 
    1. Remove the EFI No. 1 fuse from the engine room R/B and J/B.
      Fig 6: Checking Fuse (EFI Fuse)
      G04375208Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the EFI No. 1 fuse resistance.

      Standard resistance: Below 1  

    3. Reinstall the EFI No. 1 fuse.

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

    OK: Go to next step. 

  8. INSPECT ENGINE ROOM JUNCTION BLOCK ASSEMBLY (EFI RELAY) 
    1. Remove the engine room junction block.
      Fig 7: Inspecting Engine Room Junction Block Assembly (EFI Relay)
      G04375209Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the EFI relay resistance.

      Standard resistance 

      TESTER CONNECTIONS AND SPECIFIED CONDITIONS

      Tester Connections Specified Conditions
      1D-4 - 1D-6 10 k or higher
      1D-4 - 1D-6 Below 1
      (when battery voltage applied to terminals 1H-10 and 1H-2)
    3. Reinstall the engine room junction block.

    NG: REPLACE ENGINE ROOM JUNCTION BLOCK ASSEMBLY 

    OK: Go to next step. 

  9. CHECK HARNESS AND CONNECTOR (EFI RELAY - ECM, EFI RELAY - BODY GROUND) 
    1. Check the harness and connector between the EFI relay and ECM.
      Fig 8: Checking Harness And Connector Between Engine Room Junction Block (EFI Relay) And Body Ground
      G04375210Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Remove the engine room junction block.
      2. Disconnect the A24 ECM connector.
      3. Measure the resistance between the terminals of the ECM connector and engine room junction block (EFI relay).

        Standard resistance (Check for open) 

        TESTER CONNECTIONS AND SPECIFIED CONDITIONS

        Tester Connections Specified Conditions
        Engine Room Junction Block (EFI relay) (1H-10) - MREL (A24-8) Below 1

        Standard resistance (Check for short) 

        TESTER CONNECTIONS AND SPECIFIED CONDITIONS

        Tester Connections Specified Conditions
        Engine Room Junction Block (EFI relay) (1H-10) or MREL (A24-8) - Body ground 10 k or higher
    2. Check the harness and connector between the engine room junction block (EFI relay) and body ground.
      1. Measure the resistance between the terminal of the engine room junction block (EFI relay) and body ground.

        Standard resistance (Check for open) 

        TESTER CONNECTIONS AND SPECIFIED CONDITIONS

        Tester Connections Specified Conditions
        Engine Room Junction Block (EFI relay) (1H-2) - Body ground Below 1
      2. Reinstall the engine room junction block.
      3. Reconnect the ECM connector.

    OK: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    NG: CHECK AND REPLACE HARNESS AND CONNECTOR (TERMINAL +B OF ECM - BATTERY POSITIVE TERMINAL) 

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