LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2004 >> RX 330 AWD >> Repair and Diagnosis >> Engine Performance >> System >> SFI System - Diagnosis >> Fuel Pump Control Circuit >> Inspection Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

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.
      1. 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.
      Fig 1: Identifying Circuit Opening Relay Terminals
      G01395487Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard: 

      Fig 2: Specified Conditions
      G01395486Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Reinstall the circuit opening relay.
    1. OK: GO TO NEXT STEP. 
    2. NG: REPLACE CIRCUIT OPENING RELAY 
  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.
      Fig 3: Identifying Specified Terminals Of E5 And E7 ECM Connectors
      G01395489Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    Standard: 

    Fig 4: Specified Conditions
    G01395488Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. OK: REPLACE ECM (See  REPLACEMENT  in ENGINE CONTROL SYSTEM ) 
    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 ECM connector and the circuit opening relay.
      1. Disconnect the E5 ECM connector.
        Fig 5: Identifying E5 ECM Connector
        G01395494Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      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): 

        Fig 6: Specified Conditions
        G01395490Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard (Check for short): 

        Fig 7: Specified Conditions
        G01395491Courtesy 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 114 ignition switch connector.
      Fig 8: Identifying Ignition Switch Connector Terminals
      G01395496Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Inspect the IGN fuse.
        • Remove the IGN fuse from the instrument panel J/B.
        • Check for continuity in the IGN fuse.
          1. Standard: Continuity 
        • Reinstall the IGN fuse.
      2. Remove the circuit opening relay from the R/B No. 1.
        Fig 9: Identifying Circuit Opening Relay Location & Terminals
        G01395495Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Disconnect the 114 ignition switch connector.
      4. Check the resistance between the wire harness side connectors.

        Standard (Check for open): 

        Fig 10: Specified Conditions
        G01395492Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard (Check for short): 

        Fig 11: Specified Conditions
        G01395493Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      5. Reinstall the circuit opening relay.
      6. Reconnect the ignition switch connector.
    1. OK: REPLACE ECM (See  REPLACEMENT  in ENGINE CONTROL SYSTEM ) 
    2. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
  5. INSPECT FUEL PUMP 
    1. Inspect the fuel pump resistance.
      1. Measure the resistance between terminals 4 and 5.
      Fig 12: Identifying Fuel Pump Connector Terminals
      G01395497Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. 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.
      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. OK: GO TO NEXT STEP. 
    2. NG: REPLACE FUEL PUMP (See  FUEL SUCTION TUBE ASSY W/PUMP & GAGE (3MZ-FE)  ) 
  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.
        Fig 13: Identifying Circuit Opening Relay Location & Terminals
        G01395501Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Disconnect the F16 fuel pump connector.
      3. Check the resistance between the wire harness side connectors.
        Fig 14: Identifying Fuel Pump Connector Terminals
        G01395502Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard (Check for open): 

        Fig 15: Specified Conditions
        G01395498Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard (Check for short): 

        Fig 16: Specified Conditions
        G01395499Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      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): 

        Fig 17: Specified Condition Chart (Check For Open)
        G01395500Courtesy 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  in ENGINE CONTROL SYSTEM ) 

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.
      Fig 18: Identifying ECM E5 Connector Terminal
      G01395503Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Standard: 
      2. Operating noise can be heard from the circuit opening relay. 
    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.
      Fig 19: Identifying Circuit Opening Relay Terminals
      G01395505Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard: 

      Fig 20: Specified Conditions
      G01395504Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Reinstall the circuit opening relay.
      1. OK: GO TO NEXT STEP. 
      2. NG: REPLACE CIRCUIT OPENING RELAY 
  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.
      Fig 21: Identifying Specified Terminals Of E5 And E7 ECM Connectors
      G01395507Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard: 

      Fig 22: Specified Conditions
      G01395506Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. OK: REPLACE ECM (See  REPLACEMENT  in ENGINE CONTROL SYSTEM ) 
    2. NG: GO TO NEXT STEP. 
  5. 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 E5 ECM connector.
        Fig 23: Identifying ECM E5 Connector
        G01395510Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Remove the circuit opening relay from the R/B No. 1.
        Fig 24: Identifying Circuit Opening Relay
        G01395511Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Check the resistance between the wire harness side connectors.

        Standard (Check for open): 

        Fig 25: Specified Conditions
        G01395508Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard (Check for short): 

        Fig 26: Specified Conditions
        G01395509Courtesy 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 114 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.
        1. Standard: Continuity 
      • Reinstall the IGN fuse.
    2. Remove the circuit opening relay from the R/B No. 1.
    3. Disconnect the 114 ignition switch connector.
    4. Check the resistance between the wire harness side connectors.
      Fig 27: Identifying Ignition Switch Connector Terminals
      G01395512Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard (Check for open): 

      Fig 28: Specified Conditions
      G01395513Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard (Check for short): 

      Fig 29: Specified Conditions
      G01395514Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Reinstall the circuit opening relay.
    6. Reconnect the ignition switch connector.
    1. OK: REPLACE ECM (See  REPLACEMENT  in ENGINE CONTROL SYSTEM ) 
    2. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
  6. INSPECT FUEL PUMP 
    1. Inspect fuel pump resistance.
      1. Measure the resistance between terminals 4 and 5.
        Fig 30: Identifying Fuel Pump Terminals
        G01395515Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        1. 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.
      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. OK: GO TO NEXT STEP. 
    2. NG: REPLACE FUEL PUMP (See  FUEL SUCTION TUBE ASSY W/PUMP & GAGE (3MZ-FE)  ) 
  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 31: Identifying Circuit Opening Relay Location & Terminals
        G01395519Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Disconnect the F16 fuel pump connector.
      3. Check the resistance between the wire harness side connectors.
        Fig 32: Identifying Fuel Pump Connector
        G01395520Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard (Check for open): 

        Fig 33: Specified Conditions
        G01395516Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard (Check for short): 

        Fig 34: Specified Conditions
        G01395517Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      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): 

        Fig 35: Specified Condition Chart (Check For Open)
        G01395518Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Reconnect the fuel pump connector.
    1. OK: REPLACE ECM (See  REPLACEMENT  in ENGINE CONTROL SYSTEM ) 
    2. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
scientia non olet · About LEMON Manuals