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Inspection Procedure

Hand-held tester: 

  1. PERFORM ACTIVE TEST BY HAND-HELD TESTER (OPERATE CIRCUIT OPENING RELAY) 
    1. Connect the hand-held tester to the DLC3.
    2. Turn the ignition switch ON and push the hand-held tester main switch ON.
    3. Select the item "DIAGNOSIS/ENHANCED OBD II/ACTIVE TEST/FUEL PUMP/SPD".
    4. Check the relay operation while operating it with the hand-held tester.

      Standard: Operating noise can be heard from the relay. 

    1. OK: Go to step   5 
    2. NG: Go to next step. 
  2. INSPECT CIRCUIT OPENING RELAY 
    1. Remove the circuit opening relay from the R/B No.1.
    2. Inspect the circuit opening relay.

      Standard: 

      CIRCUIT OPENING RELAY

      Tester Connection Specified Condition
      1 - 2 Continuity
      3 - 5 No continuity
      3 - 5 Continuity (Apply battery voltage terminals 1 and 2)
      Fig 1: Inspecting Circuit Opening Relay
      G03017034Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Reinstall the circuit opening relay.
    1. NG: REPLACE CIRCUIT OPENING RELAY 
    2. OK: Go to next step. 
  3. INSPECT ECM (FC VOLTAGE) 
    1. Turn the ignition switch ON.
    2. Measure the voltage between the specified terminals of the E5 and E7 ECM connectors.

      Standard: 

      ECM (FC VOLTAGE)

      Tester Connection Specified Condition
      FC (E5-10) - E1 (E7-1) 9 to 14 V
      Fig 2: Inspecting ECM (FC Voltage)
      G03017035Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. OK: REPLACE ECM (See  REPLACEMENT  ) 
    2. NG: Go to next step. 
  4. CHECK HARNESS AND CONNECTOR (ECM - CIRCUIT OPENING RELAY, CIRCUIT OPENING RELAY - IGNITION) 
    1. Check the harness and the connector between the ECM connector and the circuit opening relay.
      1. Disconnect the E5 ECM connector.
      2. Remove the circuit opening relay from the R/B No. 1.
      3. Check the resistance between the wire harness side connectors.

        Standard (Check for open): 

        ECM - CIRCUIT OPENING RELAY (CHECK FOR OPEN)

        Tester Connection Specified Condition
        FC (E5-10) - Circuit opening relay (2) Below 1 Ω

        Standard (Check for short): 

        ECM - CIRCUIT OPENING RELAY (CHECK FOR SHORT)

        Tester Connection Specified Condition
        FC (E5-10) or Circuit opening relay (2) - Body ground 10 kΩ or higher
        Fig 3: Checking Harness And Connector (ECM - Circuit Opening Relay)
        G03017036Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      4. Reconnect the ECM connector.
      5. Reinstall the circuit opening relay.
    2. Check the harness and the connector between the circuit opening relay and the I14 ignition switch connector.
      1. Inspect the IGN fuse.
        • Remove the IGN fuse from the instrument panel J/B.
        • Check for continuity in the IGN fuse.

        Standard: Continuity 

        • Reinstall the IGN fuse.
      2. Remove the circuit opening relay from the R/B No. 1.
        Fig 4: Removing Circuit Opening Relay From R/B No. 1
        G03017037Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Disconnect the I14 ignition switch connector.
      4. Check the resistance between the wire harness side connectors.

        Standard (Check for open): 

        CIRCUIT OPENING RELAY - IGNITION (CHECK FOR OPEN)

        Tester Connection Specified Condition
        Circuit opening relay (1) - Ignition switch (I14-6) Below 1 Ω

        Standard (Check for short): 

        CIRCUIT OPENING RELAY - IGNITION (CHECK FOR SHORT)

        Tester Connection Specified Condition
        Circuit opening relay (1) or Ignition switch (I14-6) - Body ground 10 kΩ or higher
        Fig 5: Checking Harness And Connector (Circuit Opening Relay - Ignition)
        G03017038Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      5. Reinstall the circuit opening relay.
      6. Reconnect the ignition switch connector.
    1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
    2. OK: REPLACE ECM (See  REPLACEMENT  ). 
  5. INSPECT FUEL PUMP 
    1. Inspect the fuel pump resistance.
      1. Measure the resistance between terminals 4 and 5.

      Resistance: 0.2 to 3.0 Ω at 20°C (68°F) 

    2. Inspect the fuel pump operation
      1. Apply battery voltage to both the terminals. Check that the pump operates.
      Fig 6: Inspecting Fuel Pump
      G03017039Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    NOTE:
    • These tests must be done quickly (within 10 seconds) to prevent the coil from burning out.
    • Keep fuel pump as far away from the battery as possible. Always do the switching at the battery side.
    1. NG: REPLACE FUEL PUMP (See  FUEL SUCTION TUBE ASSY W/PUMP & GAUGE (3MZ-FE)  ) 
    2. OK: Go to next step. 
  6. CHECK HARNESS AND CONNECTOR (CIRCUIT OPENING RELAY - FUEL PUMP, FUEL PUMP - BODY GROUND) 
    1. Check the harness and the connector between the circuit opening relay and the fuel pump connector.
      1. Remove the circuit opening relay from the R/B No. 1.
        2. Fig 7: Removing Circuit Opening Relay From R/B No. 1
        G03017040Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Disconnect the F16 fuel pump connector.
      3. Check the resistance between the wire harness side connectors.

        Standard (Check for open): 

        CIRCUIT OPENING RELAY - FUEL PUMP (CHECK FOR OPEN)

        Tester Connection Specified Condition
        Circuit opening relay (3) - Fuel pump (F16-4) Below 1 Ω

        Standard (Check for short): 

        CIRCUIT OPENING RELAY - FUEL PUMP (CHECK FOR SHORT)

        Tester Connection Specified Condition
        Circuit opening relay (3) or Fuel pump (F16-4) - Body ground 10 kΩ or higher
      4. Reinstall the circuit opening relay.
      5. Reconnect the fuel pump connector.
    2. Check the harness and the connector between the fuel pump connector and the body ground.
      1. Disconnect the F16 fuel pump connector.
      2. Check the resistance between the wire harness side connectors and the body ground.

        Standard (Check for open): 

        FUEL PUMP - BODY GROUND

        Tester Connection Specified Condition
        Fuel pump (F16-5) - Body ground Below 1 Ω.
        Fig 8: Checking Harness And Connector (Fuel Pump - Body Ground)
        G03017041Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Reconnect the fuel pump connector.
    1. OK: REPAIR OR REPLACE HARNESS OR CONNECTOR 
    2. NG: REPLACE ECM (See  REPLACEMENT  ). 

OBD II scan tool (excluding hand-held tester): 

  1. CHECK FUEL PUMP OPERATION (See  ON-VEHICLE INSPECTION  ) 
    1. Check if there is pressure in the fuel inlet hose.

    HINT:

    If there is fuel pressure, you will hear the sound of fuel flowing.

    1. OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON PROBLEM SYMPTOMS TABLE (See  PROBLEM SYMPTOMS TABLE   ) 
    2. NG: Go to next step. 
  2. CHECK RELAY OPERATION (CIRCUIT OPENING RELAY) 
    1. When connecting between terminal FC of the ECM connector and the body ground, check the relay operation.

      Standard: 

      Operating noise can be heard from the circuit opening relay. 

      Fig 9: Checking Relay Operation (Circuit Opening Relay)
      G03017042Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. OK: Go to step   6 
    2. NG: Go to next step. 
  3. INSPECT CIRCUIT OPENING RELAY 
    1. Remove the circuit opening relay from the R/B No. 1.
    2. Inspect the circuit opening relay.

      Standard: 

      CIRCUIT OPENING RELAY

      Tester Connection Specified Condition
      1 - 2 Continuity
      3-5 No Continuity
      3 - 5 Continuity (Apply battery voltage terminals 1 and 2)
      Fig 10: Inspecting Circuit Opening Relay
      G03017043Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Reinstall the circuit opening relay.
    1. NG: REPLACE CIRCUIT OPENING RELAY 
    2. OK: Go to next step. 
  4. INSPECT ECM (FC VOLTAGE) 
    1. Turn the ignition switch ON.
    2. Measure the voltage between the specified terminals of the E5 and E7 ECM connectors.

      Standard: 

      ECM (FC VOLTAGE)

      Tester Connection Specified Condition
      FC (E5-10) - E1 (E7-1) 9 to 14 V
      Fig 11: Inspecting ECM (FC Voltage)
      G03017044Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. OK: REPLACE ECM (See  REPLACEMENT  ) 
    2. NG: Go to next step. 
  5. CHECK HARNESS AND CONNECTOR (ECM - CIRCUIT OPENING RELAY, CIRCUIT OPENING RELAY - IGNITION) 
    1. Check the harness and the connector between the fuel pump connector and the circuit opening relay.
      1. Disconnect the E5 ECM connector.
      2. Remove the circuit opening relay from the R/B No. 1.
      3. Check the resistance between the wire harness side connectors.

        Standard (Check for open): 

        ECM - CIRCUIT OPENING RELAY (CHECK FOR OPEN)

        Tester Connection Specified Condition
        FC (E5-10) - Circuit opening relay (2) Below 1 Ω

        Standard (Check for short): 

        ECM - CIRCUIT OPENING RELAY (CHECK FOR SHORT)

        Tester Connection Specified Condition
        FC (E5-10) or Circuit opening relay (2) - Body ground 10 kΩ or higher
        Fig 12: Checking Harness And Connector (ECM - Circuit Opening Relay)
        G03017045Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      4. Reconnect the ECM connector.
      5. Reinstall the circuit opening relay.
        Fig 13: Reinstalling Circuit Opening Relay
        G03017046Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check the harness and the connector between the circuit opening relay and the I14 ignition switch connector.
      1. Inspect the IGN fuse.
        • Remove the IGN fuse from the instrument panel J/B.
        • Check for continuity in the IGN fuse.

        Standard: Continuity 

        • Reinstall the IGN fuse.
      2. Remove the circuit opening relay from the R/B No.1.
      3. Disconnect the I14 ignition switch connector.
      4. Check the resistance between the wire harness side connectors.

        Standard (Check for open): 

        CIRCUIT OPENING RELAY - IGNITION (CHECK FOR OPEN)

        Tester Connection Specified Condition
        Circuit opening relay (1) - Ignition switch (I14-6) Below 1 Ω.

        Standard (Check for short): 

        CIRCUIT OPENING RELAY - IGNITION (CHECK FOR SHORT)

        Tester Connection Specified Condition
        Circuit opening relay (1) or Ignition switch (14-6) - Body ground 10 kΩ or higher
        Fig 14: Checking Harness And Connector (Circuit Opening Relay - Ignition)
        G03017047Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      5. Reinstall the circuit opening relay.
      6. Reconnect the ignition switch connector.
    1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
    2. OK: REPLACE ECM (See  REPLACEMENT  ). 
  6. INSPECT FUEL PUMP 
    1. Inspect fuel pump resistance.
      1. Measure the resistance between terminals 4 and 5.

      Resistance: 0.2 to 3.0 Ω at 20°C (68°F) 

    2. Inspect fuel pump operation
      1. Apply battery voltage to both the terminals. Check that the pump operates.
      Fig 15: Inspecting Fuel Pump
      G03017048Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    NOTE:
    • These tests must be done quickly (within 10 seconds) to prevent the coil from burning out.
    • Keep fuel pump as far away from the battery as possible.
    • Always do the switching at the battery side.
    1. NG: REPLACE FUEL PUMP (See  FUEL SUCTION TUBE ASSY W/PUMP & GAUGE (3MZ-FE)  ) 
    2. OK: Go to next step. 
  7. CHECK HARNESS AND CONNECTOR (CIRCUIT OPENING RELAY - FUEL PUMP, FUEL PUMP - BODY GROUND) 
    1. Check the harness and the connector between the circuit opening relay and the fuel pump connector.
      1. Remove the circuit opening relay from the R/B No.1.
        Fig 16: Removing Circuit Opening Relay From R/B No. 1
        G03017049Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Disconnect the F16 fuel pump connector.
      3. Check the resistance between the wire harness side connectors.

        Standard (Check for open): 

        CIRCUIT OPENING RELAY - FUEL PUMP (CHECK FOR OPEN)

        Tester Connection Specified Condition
        Circuit opening relay (3) - Fuel pump (F16-4) Below 1 Ω

        Standard (Check for short): 

        CIRCUIT OPENING RELAY - FUEL PUMP (CHECK FOR SHORT)

        Tester Connection Specified Condition
        Circuit opening relay (3) or Fuel pump (f16-4) - Body ground 10 kΩ or higher
      4. Reinstall the circuit opening relay.
      5. Reconnect the fuel pump connector.
    2. Check the harness and the connector between the fuel pump connector and the body ground.
      1. Disconnect the F16 fuel pump connector.
      2. Check the resistance between the wire harness side connectors and body ground.

        Standard (Check for open): 

        FUEL PUMP - BODY GROUND

        Tester Connection Specified Condition
        Fuel pump (F16-5) - Body ground Below 1 Ω
        Fig 17: Checking Harness And Connector (Fuel Pump - Body Ground)
        G03017050Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Reconnect the fuel pump connector.
    1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
    2. OK: REPLACE ECM (see  REPLACEMENT  ). 
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