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Fuel Pump Control Circuit [09/2016 - 07/2020]: Procedure

  1. PERFORM ACTIVE TEST USING TECHSTREAM (ACTIVATE THE CIRCUIT RELAY) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine / Active Test / Activate the Circuit Relay.

      Powertrain > Engine > Active Test 

      Tester Display
      Activate the Circuit Relay
    5. According to the display on the Techstream, perform the Active Test and check that fuel pump operating sounds can be heard.

      OK

      Operating sounds can be heard from the fuel pump.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  3

    Result: 

    OK 

    See step  2

  2. READ VALUE USING TECHSTREAM (ENGINE SPEED) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Put the engine in Inspection Mode (Maintenance Mode).

      Refer to INSPECTION MODE PROCEDURE [09/2016 - ]

      Powertrain > Hybrid Control > Utility 

      Tester Display
      Inspection Mode
    5. Enter the following menus: Powertrain / Engine / Data List / Engine Speed.

      Powertrain > Engine > Data List 

      Tester Display
      Engine Speed
    6. Read the values displayed on the Techstream while the engine is cranking.

      OK

      Values are displayed continuously.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [09/2016 - ] 

    Result: 

    NG 

    CHECK CRANKSHAFT POSITION SENSOR CIRCUIT. Refer to  DIAGNOSTIC TROUBLE CODE CHART [09/2016 - 01/2018]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [01/2018 - 12/2018]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [12/2018 - 05/2019]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [05/2019 - 07/2020] 

  3. INSPECT RELAY (C/OPN RELAY) 
    1. Inspect the C/OPN relay.

      Refer to PROCEDURE - Step 1

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE RELAY (C/OPN RELAY) 

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (C/OPN RELAY - ECM) 
    1. Remove the C/OPN relay from the No. 2 relay block assembly.
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2 (C/OPN relay) - A31-41 (FC) Always Below 1 Ω
      2 (C/OPN relay) or A31-41 (FC) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - C/OPN RELAY) 
    1. Disconnect the No. 1 integration relay connector.
    2. Remove the C/OPN relay from the No. 2 relay block assembly.
    3. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1A-9 - 1 (C/OPN relay) Always Below 1 Ω
      1B-4 - 5 (C/OPN relay) Always Below 1 Ω
      1A-9 or 1 (C/OPN relay) - Body ground and other terminals Always 10 kΩ or higher
      1B-4 or 5 (C/OPN relay) - Body ground and other terminals Always 10 kΩ or higher

      HINT: 

      If a short is detected in any of the above circuits, there may be a malfunction in the circuit of a connected ECU.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (C/OPN RELAY - FUEL PUMP) 
    1. Remove the C/OPN relay from the No. 2 relay block assembly.
    2. Disconnect the fuel pump connector.
    3. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      3 (C/OPN relay) - N10-4 (B) Always Below 1 Ω
      3 (C/OPN relay) or N10-4 (B) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (FUEL PUMP - BODY GROUND) 
    1. Disconnect the fuel pump connector.
    2. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      N10-5 (E) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  8

  8. INSPECT FUEL PUMP 
    1. Inspect the fuel pump.

      Refer to INSPECTION [09/2016 - 12/2018] , or refer to INSPECTION [12/2018 - ]

      HINT: 

      Perform "Inspection After Repair" after replacing the fuel pump.

      Refer to INITIALIZATION [09/2016 - 12/2018] , or refer to INITIALIZATION [12/2018 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ECM. Refer to  REMOVAL [09/2016 - 07/2020] 

    Result: 

    NG 

    REPLACE FUEL PUMP. Refer to  REMOVAL [09/2016 - 12/2018]  , or refer to  REMOVAL [12/2018 - 05/2019]  , or refer to  REMOVAL [05/2019 - 07/2020] 

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