DTC P12D0-13: Fuel Pump Control (All Phase) Circuit Open; DTC P12D1-13: Fuel Pump Control (U Phase) Circuit Open; DTC P12D2-13: Fuel Pump Control (V Phase) Circuit Open; DTC P12D3-13: Fuel Pump Control (W Phase) Circuit Open [10/2022 - ]: Procedure
WARNING: This page is about a different car, the 2025 Lexus RX 350, 2024 Lexus RX 350, and 2023 Lexus RX 350. However, it is still accessible from the selected car via links, so may be relevant.
- PERFORM ACTIVE TEST USING GTS (FUEL PUMP SINGLE PHASE ENERGIZATION)
HINT:
Make sure that the connector is properly connected. If it is not, securely connect it and check for DTCs again.
Pre-procedure1
- Disconnect the H121 fuel pump control ECU connector.
- Operate the fuel pump control ECU using the Active Test function and measure the voltage according to the value(s) in the table below.
*a Component without harness connected
(Fuel Pump Control ECU)Powertrain > Engine > Active Test
Tester Display Fuel Pump Single Phase Energization Standard Voltage
Tester Connection GTS Operation Specified Condition H121-2 (FPU) - Body ground U Phase 4.4 to 8.4 V* H121-3 (FPV) - Body ground V Phase 4.4 to 8.4 V* H121-4 (FPW) - Body ground W Phase 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 battery voltage is between 11 and 14 V (not depleted).
Result
Proceed to OK NG
Post-procedure1
- None.
Result:
NG
REPLACE FUEL PUMP CONTROL ECU. Refer to REMOVAL [10/2022 - ]
Result:
OK
See step 2
- CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU - FUEL PUMP (FOR LOW PRESSURE SIDE))
HINT:
Make sure that the connector is properly connected. If it is not, securely connect it and check for DTCs again.
Pre-procedure1
- Disconnect the fuel pump control ECU connector.
- Disconnect the fuel pump (for low pressure side) connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition Result H121-2 (FPU) - H187-3 (BLPU) Always Below 1 Ω Ω H121-3 (FPV) - H187-4 (BLPV) Always Below 1 Ω Ω H121-4 (FPW) - H187-2 (BLPW) Always Below 1 Ω Ω Result
Proceed to OK NG
Post-procedure1
- None.
Result:
OK
REPLACE FUEL PUMP (FOR LOW PRESSURE SIDE). Refer to REMOVAL [10/2022 - ]
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR