DTC P1229 Fuel Pump System

The ECM stores this DTC if the actual fuel pressure inside the common rail remains higher than the target fuel pressure, despite the ECM closing the suction control valve. This DTC indicates that the suction control valve may be stuck open, or there may be a short in its circuit.

If this DTC is stored, the ECM enters fail-safe mode and limits the engine power. The ECM continues operating in fail-safe mode until the engine switch is turned off.

Connect the GTS to the DLC3.

Turn the engine switch on (IG) and turn the GTS on.

Enter the following menus: Engine and ECT / Trouble Codes.

Read the DTCs.

Connect the GTS to the DLC3.

Turn the engine switch on (IG) and turn the GTS on.

Start the engine and warm it up.

Enter the following menus: Powertrain / Engine and ECT / Data List / Common Rail Pressure and Target Common Rail Pressure.

Check that the internal fuel pressure of the common rail assembly is within the specification below.

• OK:
• Common Rail Pressure is within 5000 kPa of Target Common Rail Pressure when engine is idling after warming up the engine.

Disconnect the suction control valve connector.

Disconnect the ECM connector.

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

• Standard Resistance:

• for LHD

  Tester Connection	Condition	Specified Condition
  z64-1 (+B) - C45- 104 (PCV+)	Always	Below 1 Ω
  z64-2 (PCV) - C45-105 (PCV-)	Always	Below 1 Ω
  z64-1 (+B) or C45- 104 (PCV+) - Body ground	Always	10 kΩ or higher
  z64-2 (PCV) or C45-105 (PCV-) - Body ground	Always	10 kΩ or higher

• Standard Resistance:

• for RHD

  Tester Connection	Condition	Specified Condition
  z64-1 (+B) - C46- 104 (PCV+)	Always	Below 1 Ω
  z64-2 (PCV) - C46-105 (PCV-)	Always	Below 1 Ω
  z64-1 (+B) or C46- 104 (PCV+) - Body ground	Always	10 kΩ or higher
  z64-2 (PCV) or C46-105 (PCV-) - Body ground	Always	10 kΩ or higher

Reconnect the suction control valve connector.

Reconnect the ECM connector.

Repair or replace the harness or connector.

Connect the GTS to the DLC3.

Turn the engine switch on (IG) and turn the GTS on.

Enter the following menus: Powertrain / Engine and ECT / Active Test / Test the Fuel Leak / Data List / Common Rail Pressure and Target Common Rail Pressure.

Take a snapshot with the GTS during the Active Test.

Measure the difference between the target fuel pressure (Target Common Rail Pressure) and the actual fuel pressure (Common Rail Pressure) when the "Test the Fuel Leak" Active Test is performed ().

• HINT:

• In order to obtain an exact measurement, perform the Active Test 5 times and measure the difference once each time the Active Test is performed.

• OK:
• The difference between the target fuel pressure and the actual fuel pressure 2 seconds after the Active Test starts is less than 10000 kPa.

• HINT:

Clean the fuel filter case and replace the fuel filter.

• HINT:

• Be sure to clean the inside of the fuel filter case as the fuel injectors may not operate properly if the fuel filter is installed with foreign matter remaining inside the fuel filter case.

Replace the fuel supply pump assembly ().

Bleed the air from the fuel system ().

Perform PM forced regeneration ().

• HINT:

• When fuel lines are disconnected, air may enter the fuel lines, leading to engine starting trouble. Therefore, perform forced regeneration and bleed the air from the fuel lines.

Perform supply pump initialization ().

Connect the GTS to the DLC3.

Clear the DTCs ().

Turn the engine switch off for 30 seconds or more.

Start the engine.

Idle the engine for 60 seconds, and then run it at 2500 rpm without load for 60 seconds.

Confirm that the DTC is not output again.

• HINT:

• Perform the following procedure using the GTS to determine whether or not the DTC judgment has been carried out.