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Inspection Procedure: Notes

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 engine room J/B.
    2. Inspect the circuit opening relay.
      Fig 1: Inspecting Circuit Opening Relay
      G02933352Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard: 

      Fig 2: Terminal Specified Condition Table
      G02933353Courtesy 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 terminals of the E4 and E6 ECM connectors.
      Fig 3: Identifying E4 & E6 ECM Connector Terminals For Measuring Voltage
      G02933354Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard: 

      SYMBOLS SPECIFIED CONDITION

      Symbols (Terminal No.) Specified condition
      FC (E4-10) - E1 (E6-1) 9 to 14 V
    1. OK: CHECK AND REPLACE ECM (See  ELECTRONIC CIRCUIT INSPECTION PROCEDURE  ) 
    2. NG: Go to next step. 
  4. CHECK HARNESS AND CONNECTOR (ECM - CIRCUIT OPENING RELAY, CIRCUIT OPENING RELAY - IGNITION SWITCH) 
    1. Check the harness and the connector between the fuel pump connector and the circuit opening relay.
      1. Disconnect the E4 ECM connector.
        2. Fig 4: Disconnecting E4 ECM Connector
        G02933355Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Remove the circuit opening relay from the engine room J/B.
        3. Fig 5: Removing Circuit Opening Relay
        G02933356Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Check for continuity between the wire harness side connectors.

        Standard (Check for open): 

        SYMBOLS SPECIFIED CONDITION (FOR OPEN)

        Symbols (Terminal No.) Specified condition
        FC (E4-10) - Circuit opening relay (2) Continuity

        Standard (Check for short): 

        SYMBOLS SPECIFIED CONDITION

        Symbols (Terminal No.) Specified condition
        FC (E4-10) or Circuit opening relay (2) - Body ground No continuity
      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 ignition switch.
      1. Remove the circuit opening relay from the engine room J/B.
      2. Disconnect the ignition switch connector.
        3. Fig 6: Identifying Ignition Switch Connector Terminals
        G02933357Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Check for continuity between the wire harness side connectors.

        Standard (Check for open): 

        SYMBOLS SPECIFIED CONDITION

        Symbols (Terminal No.) Specified condition
        Circuit opening relay (1) - Ignition switch (6) Continuity

        Standard (Check for short): 

        SYMBOL SPECIFIED CONDITION (FOR SHORT)

        Symbols (Terminal No.) Specified condition
        Circuit opening relay (1) or Ignition switch (6) - Body ground No continuity
      4. Reinstall the circuit opening relay.
      5. Reconnect the ignition switch connector.
    1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
    2. OK: CHECK AND REPLACE ECM (See  ELECTRONIC CIRCUIT INSPECTION PROCEDURE  ) 
  5. INSPECT FUEL PUMP 
    1. Inspect fuel pump resistance.
      1. Measure the resistance between terminals 4 and 5.
        Fig 7: Identifying Fuel Pump Connector Terminals For Measuring Resistance
        G02933358Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        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.
    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  INSPECTION  ) 
    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 engine room J/B.
        2. Fig 8: Removing Circuit Opening Relay
        G02933359Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Disconnect the fuel pump connector.
        3. Fig 9: Identifying Full Pump Connector Terminals For Checking Continuity
        G02933360Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Check for continuity between the wire harness side connectors.

        Standard (Check for open): 

        SYMBOLS SPECIFIED CONDITION

        Symbols (Terminal No.) Specified condition
        Circuit opening relay (3) - Fuel pump (4) Continuity

        Standard (Check for short): 

        SYMBOLS SPECIFIED CONDITION

        Symbols (Terminal No.) Specified condition
        Circuit opening relay (3) or Fuel pump (4) - Body ground No continuity
      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 fuel pump connector.
      2. Check for continuity between the wire harness side connectors and the body ground.

        Standard (Check for open): 

        SYMBOLS SPECIFIED CONDITION

        Symbols (Terminal No.) Specified condition
        Fuel pump (5) - Body ground Continuity
      3. Reconnect the fuel pump connector.
    1. OK: REPAIR OR REPLACE HARNESS OR CONNECTOR 
    2. NG: REPLACE ECM (See  ELECTRONIC CIRCUIT INSPECTION PROCEDURE  ) 
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