СИСТЕМА ECD, Diagnostic DTC:P0088

DTC Code	DTC Name
P0088	Fuel Rail / System Pressure - Too High

DESCRIPTION

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Memory
P0088	Fuel Rail / System Pressure - Too High	The fuel pressure of the common rail exceeds 220000 kPa (2243.3 kgf/cm², 31911 psi) (1 trip detection logic).	Suction control valve Pressure discharge valve (built into common rail assembly) Open or short in supply pump assembly (suction control valve) circuit Fuel pressure sensor (built into common rail assembly) ECM	Comes on	DTC stored

Table 1. Related Data List
DTC No.	Data List
P0088	Fuel Press Target Common Rail Pressure Injection Pressure Correction Target Pump SCV Current Pressure Discharge Valve

Tip:

For more information on the supply pump assembly (suction control valve) and common rail system, refer to System Description.

Click hereНажмите здесь

When DTC P0088 is stored, check the internal fuel pressure of the common rail assembly by entering the following menus: Powertrain / Engine and ECT / Data List / All Data / Fuel Press.

Table 2. Reference
Engine Speed	Fuel Press
Idling	Approximately 27000 to 45000 kPa
3000 rpm (No engine load)	Approximately 44000 to 78000 kPa

When there is an operating problem with the supply pump assembly (when Fuel Press is more than Target Common Rail Pressure due to a problem with the closing of the suction control valve), the values of Injection Pressure Correction and Target Pump SCV Current decrease.

Check "Fuel Press", "Target Common Rail Pressure", "Target Pump SCV Current" and "Pressure Discharge Valve" in the freeze frame data.

MONITOR DESCRIPTION

P0088 (Internal fuel pressure too high):
The ECM stores this DTC if the fuel pressure inside the common rail assembly is higher than 220000 kPa (2243.3 kgf/cm², 31911 psi). This DTC indicates that: 1) the suction control valve may be stuck open, or 2) there may be a short in the suction control valve circuit.

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

CONFIRMATION DRIVING PATTERN

DTC No.	DTC Detection Drive Pattern
P0088	After idling for 60 seconds, repeat quick engine speed accelerations (from idling to 2500 rpm) for 30 seconds

WIRING DIAGRAM

Table 3.
*a	Suction Control Valve

CAUTION / NOTICE / HINT

Note:

After replacing the ECM, the new ECM needs registration (Click here) and initialization (Click hereНажмите здесь).

After replacing the suction control valve, the ECM needs initialization.

Click hereНажмите здесь

Tip:

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.

PROCEDURE

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

Connect the GTS to the DLC3.

Turn the ignition switch to ON and turn the GTS on.

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

Read the DTCs.

Powertrain > Engine and ECT > Trouble Codes

Result

Result	Proceed to
DTC P0088 is output	A
DTC P0088 and other DTCs are output	B

Tip:

If any DTCs other than P0088 are output, troubleshoot those DTCs first.

GO TO DTC CHART Click here Нажмите здесь

CHECK FREEZE FRAME DATA (FUEL PRESS)

Connect the GTS to the DLC3.

Turn the ignition switch to ON and turn the GTS on.

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

Record the stored DTC and freeze frame data.

Powertrain > Engine and ECT > Trouble Codes

Result

Result	Proceed to
Except below	A
Value of Fuel Press is shifting towards 160000 kPa or higher in 3rd and 4th set of freeze frame data	B

Нажмите здесь

GO TO STEP 4

CHECK HARNESS AND CONNECTOR (FUEL PRESSURE SENSOR - ECM)

Tip:

If the MIL has illuminated before in the past, clear the DTC using the GTS before performing this inspection.

Click hereНажмите здесь

Check it the MIL illuminates up when vibration is applied to the wire harness and connectors between the fuel pressure sensor and ECM.

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

Result

Result	Proceed to
MIL does not come on	A
MIL comes on	B

Нажмите здесь

REPLACE SUCTION CONTROL VALVE

Replace the suction control valve.

Click hereНажмите здесь

Tip:

Before replacing the suction control valve, check that the wire harness between the suction control valve and ECM is not shorted to ground.

When there is a malfunction in the wire harness, Target Pump SCV Current is outside the range of 923 to 1123 mA when idling, and outside the range of 1013 to 1212 mA when the engine is running at 2500 rpm without load.

If there are no problems with the engine condition during idling, it is not necessary to perform the above wire harness inspection.

When the wire harness between the suction control valve and ECM is not shorted to ground, it can be assumed that DTC P0088 was stored due to a malfunction in the operation of the suction control valve. Therefore, it is necessary to replace the suction control valve.

Result

Proceed to
NEXT

BLEED AIR FROM FUEL SYSTEM

Bleed the air from the fuel system.

Click hereНажмите здесь

Result

Proceed to
NEXT

PERFORM SUPPLY PUMP INITIALIZATION

Perform the supply pump initialization.

Click hereНажмите здесь

Result

Proceed to
NEXT

CHECK DTC OUTPUT

Connect the GTS to the DLC3.

Turn the ignition switch to ON.

Turn the GTS on.

Clear the DTCs.

Powertrain > Engine and ECT > Clear DTCs

Turn the ignition switch off and wait for 30 seconds or more.

Start the engine and turn the GTS on.

After idling for 60 seconds, repeat quick engine speed accelerations (from idling to 2500 rpm) for 30 seconds.

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

Read the pending DTCs.

Powertrain > Engine and ECT > Trouble Codes

Tip:

If no pending DTCs are output, proceed to the next step to check "All Readiness".

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

Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
Powertrain > Engine and ECT > Utility
Tester Display
All Readiness
Input DTC P0088.
Check the DTC judgment result.
Result
GTS Display Result Proceed to
Pending DTC DTC P0088 is output A
All Readiness NORMAL B
ABNORMAL A
Tip:
If STATUS is INCOMPLETE or N/A, race the engine to 2500 rpm repeatedly for 30 seconds and increase the idling time.

Tester Display
All Readiness

END

REPLACE ECM

Replace the ECM.

Click hereНажмите здесь

Result

Proceed to
NEXT

Нажмите здесь

GO TO STEP 13

REPAIR OR REPLACE HARNESS OR CONNECTOR

Repair or replace the harness or connector.

Result

Proceed to
NEXT

CHECK HARNESS AND CONNECTOR (FUEL PRESSURE SENSOR - ECM)

Tip:

If the MIL has illuminated before in the past, clear the DTC using the GTS before performing this inspection.

Click hereНажмите здесь

Check it the MIL illuminates up when vibration is applied to the wire harness and connectors between the fuel pressure sensor and ECM.

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

Result

Result	Proceed to
MIL comes on	A
MIL does not come on	B

Нажмите здесь

GO TO STEP 13

REPLACE COMMON RAIL ASSEMBLY

Replace the common rail assembly.

Click hereНажмите здесь

Result

Proceed to
NEXT

BLEED AIR FROM FUEL SYSTEM

Bleed the air from the fuel system.

Click hereНажмите здесь

Result

Proceed to
NEXT

CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

Connect the GTS to the DLC3.

Turn the ignition switch to ON.

Turn the GTS on.

Clear the DTCs.

Powertrain > Engine and ECT > Clear DTCs

Turn the ignition switch off and wait for 30 seconds or more.

Start the engine and turn the GTS on.

After idling for 60 seconds, repeat quick engine speed accelerations (from idling to 2500 rpm) for 30 seconds.

Confirm that the DTC is not output.

Tip:

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

Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
Powertrain > Engine and ECT > Utility
Tester Display
All Readiness
Input DTC P0088.
Check that STATUS is NORMAL.

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

Result

Proceed to
NEXT

END