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DTC P12D5-01: Fuel Pump Control General Electrical Failure [11/2024 - ]: Procedure

WARNING: This page is about a different variant/trim than selected.
  1. INSPECT FUEL PUMP CONTROL ECU 
    GTY898273Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Component without harness connected
    (Fuel Pump Control ECU)    		 - -
    1. Remove the fuel pump control ECU.

      Refer to REMOVAL [12/2019 - ]

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      M53-2 (FPU) - M54-3 (GND) Always 2 kΩ or higher
      M53-3 (FPV) - M54-3 (GND) Always 2 kΩ or higher
      M53-4 (FPW) - M54-3 (GND) Always 2 kΩ or higher

      HINT: 

      This procedure checks for an internal short of the fuel pump control ECU when its transistor is stuck on.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE FUEL PUMP CONTROL ECU 

    Refer to REMOVAL [12/2019 - ]

    Result: 

    OK 

    See step  2

  2. PERFORM ACTIVE TEST USING GTS (FUEL PUMP SINGLE PHASE ENERGIZATION) 
    GTY935743Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Component without harness connected
    (Fuel Pump Control ECU)
    1. Disconnect the M53 fuel pump control ECU connector.
    2. Operate the fuel pump control ECU using the Active Test function and measure the voltage according to the value(s) in the table below.

      Powertrain > Engine > Active Test 

      Tester Display
      Fuel Pump Single Phase Energization

      Standard Voltage

      Tester Connection GTS Operation Specified Condition
      M53-2 (FPU) - Body ground U Phase 4.4 to 8.4 V*
      M53-3 (FPV) - Body ground 8 to 15.5 V
      M53-4 (FPW) - Body ground 8 to 15.5 V
      M53-2 (FPU) - Body ground V Phase 8 to 15.5 V
      M53-3 (FPV) - Body ground 4.4 to 8.4 V*
      M53-4 (FPW) - Body ground 8 to 15.5 V
      M53-2 (FPU) - Body ground W Phase 8 to 15.5 V
      M53-3 (FPV) - Body ground 8 to 15.5 V
      M53-4 (FPW) - Body ground 4.4 to 8.4 V*

      HINT: 

      • *: This Active Test limits the fuel pump control ECU output duty cycle to 50%. Therefore, the output voltage of the fuel pump control ECU will be approximately 50% of the power source voltage (+B terminal).
      • Before performing this inspection, check that the auxiliary battery voltage is between 11 and 14 V (not depleted).

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE FUEL PUMP CONTROL ECU 

    Refer to REMOVAL [12/2019 - ]

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU - FUEL PUMP (FOR LOW PRESSURE SIDE)) 
    1. Disconnect the fuel pump control ECU connector.
    2. Disconnect the fuel pump (for low pressure side) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      M53-2 (FPU) or r2-3 (BLPU) - Body ground and other terminals Always 10 kΩ or higher
      M53-3 (FPV) or r2-4 (BLPV) - Body ground and other terminals Always 10 kΩ or higher
      M53-4 (FPW) or r2-2 (BLPW) - Body ground and other terminals Always 10 kΩ or higher

      HINT: 

      Perform "Inspection After Repair" after replacing the fuel pump (for low pressure side).

      Refer to INITIALIZATION [10/2021 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE FUEL PUMP (FOR LOW PRESSURE SIDE) 

    Refer to REMOVAL [11/2023 - ]

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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