Dtc P0088 Fuel Rail / System Pressure - Too High

DESCRIPTION

MONITOR DESCRIPTION

INSPECTION PROCEDURE

CHECK FOR ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0088)

CHECK FREEZE FRAME DATA (COMMON RAIL PRESSURE)

INSPECT ECM (FUEL PRESSURE SENSOR OUTPUT VOLTAGE)

PERFORM ACTIVE TEST USING GTS (ACTIVATE THE PRE-STROKE CONTROL VALVE)

REPLACE FUEL SUPPLY PUMP ASSEMBLY

BLEED AIR FROM FUEL SYSTEM

CHECK DTC OUTPUT

REPLACE ECM

REPAIR OR REPLACE HARNESS OR CONNECTOR

INSPECT ECM (FUEL PRESSURE SENSOR OUTPUT VOLTAGE)

REPLACE COMMON RAIL ASSEMBLY

BLEED AIR FROM FUEL SYSTEM

CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

DESCRIPTION

HINT:

1. For more information on the fuel supply pump assembly (pre-stroke control valve) and common rail system, refer to System Description (LandCruiser RM000000XSN04PX.html).
   
2. When DTC P0088 is stored, check the internal fuel pressure of the common rail by entering the following menus: Powertrain / Engine and ECT / Data List / Common Rail Pressure.
   
   

   Reference

   Engine Speed	Common Rail Pressure
   Idling	Approximately 30000 to 50000 kPa
   3000 rpm (No engine load)	Approximately 80000 to 110000 kPa

3. Check "Common Rail Pressure" and "Target Common Rail Pressure" in the freeze frame data.
   

MONITOR DESCRIPTION

1. P0088 (Internal fuel pressure too high):
   The ECM stores this DTC if the fuel pressure inside the common rail assembly is higher than 240000 kPa (2447 kgf/cm², 34800 psi). This DTC indicates that: 1) the pre-stroke control valve may be stuck open, or 2) there may be a short in the pre-stroke control valve 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 off.
   

INSPECTION PROCEDURE

NOTICE:

After replacing the ECM, the new ECM needs registration (LandCruiser RM0000012XK0AVX.html) and initialization (LandCruiser RM000000TIN08IX.html).

HINT:

Read freeze frame data using the GTS. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, and other data from the time the malfunction occurred.

1. Connect the GTS to the DLC3.
   

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

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

4. Read Current DTCs.
   
   

   Result

   Result	Proceed to
   DTC P0088 is output	A
   DTC P0088 and "P0190, P0192 and/or P0193" are output	B

   HINT:

   When there is an open circuit in the fuel pressure sensor circuit, the fuel pressure sensor outputs the maximum value. Therefore, P0088 may be stored together with DTCs which indicate common rail fuel pressure sensor circuit malfunctions.

1. Connect the GTS to the DLC3.
   

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

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

4. Record the stored DTCs and freeze frame data.
   
   

   Result

   Result	Proceed to
   Value of Common Rail Pressure is shifting towards 200000 kPa or higher in 3rd and 4th set of freeze frame data	B
   Except above	A

1. Connect the positive (+) probe of an oscilloscope to the fuel pressure sensor input terminal of the ECM connector and the negative (-) probe to the body ground.
   

   Text in Illustration

   *a	Component with harness connected (ECM)

2. Turn the engine switch on (IG).
   

3. Check for any noise in the waveform when vibration is applied to the wire harness and connectors between the fuel pressure sensor and ECM.
   

   
   
   
   
   

   Text in Illustration

   *1	Engine	*2	Common Rail Assembly (Fuel Pressure Sensor)
   *3	Engine Wire	*4	Wire to Wire
   *5	ECM	-	-
   *a	Vibration Method (Reference)	-	-

   
   
   
   
   

   Standard Voltage:

   
   

   Tester Connection	Condition	Specified Condition
   C151-18 (PCR1) - Body ground	Vibration is applied to the wire harness and connectors	No noise in the waveform

1. Connect the GTS to the DLC3.
   

2. Turn the engine switch on (IG).
   

3. Turn the GTS on.
   

4. Enter the following menus: Powertrain / Engine and ECT / Active Test / Activate the Pre-stroke Control Valve
   

5. Perform the Active Test and check that operation sounds can be heard from the pre-stroke control valve.
   

   HINT:

   1. Perform this procedure with the engine stopped and check the operation sounds from outside the vehicle.
      
   2. Check in a quiet location with the hood opened, as the operation sound is difficult to hear.
      
   3. In order to distinguish between the operation sounds of other actuators, use the GTS to turn the Active Test on and off several times, and check for operation sounds that are synchronized with the on and off operations.
      

   OK:

   Operation sounds occur each time the Active Test is performed every 0.5 seconds.
   

1. Replace the fuel supply pump assembly (LandCruiser RM000005UHX000X.html).
   

1. Bleed the air from the fuel system (LandCruiser RM000002SY803FX_01_0002.html).
   

1. Connect the GTS to the DLC3.
   

2. Clear the DTCs (LandCruiser RM000000PDK1ENX.html).
   

3. Turn the engine switch off for 30 seconds or more.
   

4. Turn the engine switch on (IG) and start the engine.
   

5. After idling for 60 seconds, increase the engine speed from idling to 2500 rpm repeatedly for 30 seconds.
   

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

7. 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.

   1. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
      

   2. Input DTC P0088.
      

   3. Check the DTC judgment result.
      
      

      Result

      GTS Display	Result	Proceed to
      Pending DTC	DTC P0088 is output	A
      All Readiness	NORMAL	B
      	ABNORMAL	A

      HINT:

      If STATUS is INCOMPLETE or N/A, race the engine to 2500 rpm repeatedly for 30 seconds and increase the idling time.

1. Replace the ECM (LandCruiser RM0000013Z002DX.html).
   

1. Repair or replace the harness or connector.
   

1. Connect the positive (+) probe of an oscilloscope to the fuel pressure sensor input terminal of the ECM connector and the negative (-) probe to the body ground.
   

   Text in Illustration

   *a	Component with harness connected (ECM)

2. Turn the engine switch on (IG).
   

3. Check for any noise in the waveform when vibration is applied to the wire harness and connectors between the fuel pressure sensor and ECM.
   

   Standard Voltage:

   Tester Connection	Condition	Specified Condition
   C151-18 (PCR1) - Body ground	Vibration is applied to the wire harness and connectors	No noise in the waveform

1. Replace the common rail assembly (LandCruiser RM000005UI0000X.html).
   

1. Bleed the air from the fuel system (LandCruiser RM000002SY803FX_01_0002.html).
   

1. Connect the GTS to the DLC3.
   

2. Clear the DTCs (LandCruiser RM000000PDK1ENX.html).
   

3. Turn the engine switch off for 30 seconds or more.
   

4. Turn the engine switch on(IG) and start the engine.
   

5. After idling for 60 seconds, increase the engine speed from idling to 2500 rpm repeatedly for 30 seconds.
   

6. 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.

   1. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
      

   2. Input DTC P0088.
      

   3. Check that STATUS is NORMAL. If STATUS is INCOMPLETE or N/A, race the engine to 2500 rpm repeatedly for 30 seconds and increase the idling time.