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Inspection Procedure

  1. INSPECT ECM (+B VOLTAGE) 
    1. Turn the ignition switch to ON.
    2. Measure the voltage between the terminals of the ECM connectors.

      Standard Voltage 

      TESTER CONNECTIONS AND SPECIFIED CONDITION TABLE

      Tester Connections Specified Conditions
      +B (E8-1) - E1 (E4-3) 9 to 14 V

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

    Fig 1: Identifying E4 ECM Connector Terminals
    G04407855Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND) 
    1. Disconnect the negative battery cable.
    2. Disconnect the E4 ECM connector.
    3. Check the resistance.

      Standard Resistance 

      TESTER CONNECTIONS AND SPECIFIED CONDITION TABLE

      Tester Connections Specified Conditions
      E1 (E4-3) - Body ground Below 1 Ω
    4. Reconnect the ECM connector.
    5. Reconnect the negative battery cable.
      Fig 2: Disconnecting E4 ECM Connector
      G04407856Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  3. INSPECT ECM (IGSW VOLTAGE) 
    1. Turn the ignition switch to ON.
    2. Measure the voltage between the terminals of the ECM connectors.

      Standard Voltage 

      TESTER CONNECTIONS AND SPECIFIED CONDITION TABLE

      Tester Connections Specified Conditions
      IGSW (E8-9) - E1 (E4-3) 9 to 14 V

    OK: Go to step   6 

    Fig 3: Identifying E4 ECM Connector Terminals
    G04407857Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to next step 

  4. CHECK FUSE (AM2 AND IGN) 
    1. Check the AM2 fuse.
      1. Remove the AM2 fuse from the engine room R/B.
      2. Check the AM2 fuse resistance.

        Standard Resistance: 

        Below 1 Ω 

      3. Reinstall the AM2 fuse.
    2. Check the IGN fuse.
      1. Remove the IGN fuse from the driver side J/B.
      2. Check the IGN fuse resistance.

        Standard Resistance: 

        Below 1 Ω 

      3. Reinstall the IGN fuse.

    NG: CHECK FOR SHORT IN ALL HARNESS AND COMPONENTS CONNECTED TO FUSE 

    Fig 4: Identifying IGN Fuse
    G04407858Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  5. INSPECT IGNITION OR STARTER SWITCH ASSEMBLY 
    1. Disconnect the I7 ignition switch connector.
    2. Check the resistance.

      Standard Resistance 

      TESTER CONNECTIONS AND SPECIFIED CONDITION TABLE

      Ignition Switch Positions Tester Connections Specified Conditions
      LOCK All Terminals 10 kΩ or higher
      ACC 2-4 Below 1 Ω
      ON 1-4, 1-6, 2-4, 3-4, 5-6 Below 1 Ω
      START 1-4, 3-4, 5-6, 5-7 Below 1 Ω
    3. Reconnect the ignition switch connector.
      Fig 5: Identifying Ignition Switch Connector Terminals
      G04407859Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE IGNITION OR STARTER SWITCH ASSEMBLY 

    OK: CHECK AND REPAIR HARNESS AND CONNECTOR (BATTERY - IGNITION SWITCH, IGNITION SWITCH - ECM) 

  6. INSPECT ECM (MREL VOLTAGE) 
    1. Turn the ignition switch to ON.
    2. Measure the voltage between the terminals of the ECM connectors.

      Standard Voltage 

      TESTER CONNECTIONS AND SPECIFIED CONDITION TABLE

      Tester Connections Specified Conditions
      MREL (E8-8) - E1 (E4-3) 9 to 14 V

    NG: REPLACE ECM 

    Fig 6: Identifying E4 & E8 ECM Connector Terminals
    G04407860Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  7. CHECK FUSE (EFI) 
    1. Remove the EFI fuse from the engine room R/B.
    2. Check the EFI fuse resistance.

      Standard Resistance: 

      Below 1 Ω 

    3. Reinstall the EFI fuse.

    NG: CHECK FOR SHORT IN ALL HARNESS AND COMPONENTS CONNECTED TO FUSE 

    Fig 7: Identifying EFI Fuse
    G04407861Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  8. INSPECT EFI RELAY 
    1. Remove the EFI relay from the engine room R/B.
    2. Check the EFI relay resistance.

      Standard Resistance 

      TESTER CONNECTIONS AND SPECIFIED CONDITION TABLE

      Tester Connections Specified Conditions
      3 - 5 10 kΩ or higher
      3 - 5 Below 1 Ω
      (when battery voltage applied to terminals 1 and 2)
    3. Reinstall the EFI relay.
      Fig 8: Checking EFI Relay Resistance
      G04407862Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE EFI RELAY 

    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.
      1. Remove the EFI relay from the engine room R/B.
      2. Disconnect the E8 ECM connector.
      3. Check the resistance.

        Standard Resistance (Check for open) 

        TESTER CONNECTIONS AND SPECIFIED CONDITION TABLE

        Tester Connections Specified Conditions
        Engine room R/B (EFI relay terminal 1) - MREL (E8-8) Below 1 Ω
        Engine room R/B (EFI relay terminal 3) - +B (E8-1) Below 1 Ω

        Standard Resistance (Check for short) 

        TESTER CONNECTIONS AND SPECIFIED CONDITION TABLE

        Tester Connections Specified Conditions
        Engine room R/B (EFI relay terminal 1) or MREL (E8-8) - Body ground 10 kΩ or higher
        Engine room R/B (EFI relay terminal 3) or +B (E8-1) - Body ground 10 kΩ or higher
      4. Reconnect the ECM connector.
      5. Reinstall the EFI relay.
    2. Check the harness and connector between the EFI relay and body ground.
      1. Remove the EFI relay from the engine room R/B.
        Fig 9: Disconnecting E8 ECM Connector Terminals
        G04407863Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Check the resistance.

        Standard Resistance (Check for open): 

        TESTER CONNECTIONS AND SPECIFIED CONDITION TABLE

        Tester Connections Specified Conditions
        Engine room R/B (EFI relay terminal 2) - Body ground Below 1 Ω
      3. Reinstall the EFI relay.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: CHECK AND REPLACE HARNESS AND CONNECTOR (TERMINAL 5 OF EFI RELAY - BATTERY POSITIVE TERMINAL) 

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