DTC P12D4-19: Fuel Pump Control Circuit Current Above Threshold; DTC P12D4-1D: Fuel Pump Control Circuit Current Out of Range [11/2024 - ]: Procedure

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

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) - Other terminals	Always	10 kΩ or higher
   M53-3 (FPV) or r2-4 (BLPV) - Other terminals	Always	10 kΩ or higher
   M53-4 (FPW) or r2-2 (BLPW) - Other terminals	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  4

Refer to REMOVAL [11/2023 - ]

HINT: 

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

Refer to INITIALIZATION [10/2021 - ]

Result

Result: 

NEXT 

See step  5

1. Clear the DTCs.

   Powertrain > Engine > Clear DTCs 

2. Turn the ignition switch off and wait for at least 30 seconds.

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  6

1. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
2. Read the DTCs.

   Powertrain > Engine > Trouble Codes 

   OK

   DTCs are not output.

   Result

   Proceed to
   NEXT

Result: 

NEXT 

END