DTC P0627-14: Fuel Pump "A" Control Circuit Short to Ground or Open [10/2022 - ]: Procedure

Pre-procedure1

• Disconnect the fuel pump control ECU connector.
• Turn the ignition switch to ON.

• Measure the voltage according to the value(s) in the table below.

  Standard Voltage

  Tester Connection	Condition	Specified Condition	Result
  H122-1 (+B) - H122-3 (GND)	Ignition switch ON	11 to 14 V	V

  Result

  Proceed to
  OK
  NG

Post-procedure1

• None.

Result: 

NG 

See step  4

Result: 

OK 

See step  2

Pre-procedure1

• Disconnect the fuel pump control ECU connector.

• Operate the fuel pump control ECU using the Active Test function and measure the resistance according to the value(s) in the table below.

  Powertrain > Engine > Active Test 

  Tester Display
  Fuel Pump Single Phase Energization

  Standard Resistance

  Tester Connection	GTS Operation	Specified Condition
  H122-2 (FPC) - Body ground	Before Active Test → During Active Test	Before Active Test: Resistance is stable → During Active Test: Resistance fluctuates*

  HINT: 

  *: Using the Active Test, duty control of the transistors in the ECM will be performed. Due to the duty control, resistance of the FPC terminal will be unstable during the Active Test. If the resistance is stable before the Active Test and fluctuates while performing the Active Test, it can be determined that the transistor is operating. If the transistor does not operate during the Active Test, the ECM may be malfunctioning.

  Result

  Proceed to
  OK
  NG

Post-procedure1

• None.

Result: 

OK 

REPLACE FUEL PUMP CONTROL ECU. Refer to  REMOVAL [10/2022 - ] 

Result: 

NG 

See step  3

Pre-procedure1

• Disconnect the fuel pump control ECU connector.
• Disconnect the ECM connector.

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

  Standard Resistance

  Tester Connection	Condition	Specified Condition	Result
  H122-2 (FPC) - A16-4 (FPC)	Always	Below 1 Ω	Ω
  H122-2 (FPC) or A16-4 (FPC) - Body ground	Always	10 kΩ or higher	kΩ

  Result

  Proceed to
  OK
  NG

Post-procedure1

• None.

Result: 

OK 

REPLACE ECM. Refer to  REMOVAL [10/2022 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Pre-procedure1

• Disconnect the fuel pump control ECU connector.

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

  Standard Resistance

  Tester Connection	Condition	Specified Condition	Result
  H122-3 (GND) - Body ground	Always	Below 1 Ω	Ω

  Result

  Proceed to
  OK
  NG

Post-procedure1

• None.

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  5

Refer to PROCEDURE - Step 4

Result

Result: 

NG 

REPLACE EFI-MAIN NO. 2 RELAY 

Result: 

OK 

See step  6

Pre-procedure1

• Remove the EFI-MAIN NO. 2 relay from the No. 1 engine room relay block and No. 1 junction block assembly.

• Measure the voltage according to the value(s) in the table below.

  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

  *1	No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly
  *2	EFI-MAIN NO. 2 Relay

  Standard Voltage

  Tester Connection	Condition	Specified Condition	Result
  3 (EFI-MAIN NO. 2 relay) - Body ground	Always	11 to 14 V	V

  Result

  Proceed to
  OK
  NG

Post-procedure1

• None.

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - EFI-MAIN NO. 2 RELAY) 

Result: 

OK 

See step  7

Pre-procedure1

• Remove the EFI-MAIN NO. 2 relay from the No. 1 engine room relay block and No. 1 junction block assembly.

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

  Standard Resistance

  Tester Connection	Condition	Specified Condition	Result
  1 (EFI-MAIN NO. 2 relay) - Body ground	Always	Below 1 Ω	Ω

  Result

  Proceed to
  OK
  NG

Post-procedure1

• None.

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  8

Pre-procedure1

• Disconnect the fuel pump control ECU connector.
• Remove the EFI-MAIN NO. 2 relay from the No. 1 engine room relay block and No. 1 junction block assembly.

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

  Standard Resistance

  Tester Connection	Condition	Specified Condition	Result
  H122-1 (+B) - 5 (EFI-MAIN NO. 2 relay)	Always	Below 1 Ω	Ω
  H122-1 (+B) or 5 (EFI-MAIN NO. 2 relay) - Body ground and other terminals	Always	10 kΩ or higher	kΩ

  Result

  Proceed to
  OK
  NG

Post-procedure1

• None.

Result: 

OK 

REPAIR OR REPLACE HARNESS OR CONNECTOR (EFI-MAIN NO. 1 RELAY - EFI-MAIN NO. 2 RELAY) 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR