Dtc P0088 Fuel Rail / System Pressure - Too High

DESCRIPTION

MONITOR DESCRIPTION

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK OTHER DTC OUTPUT (IN ADDITION TO DTC P0088 AND/OR P1229)

INSPECT SUPPLY PUMP ASSEMBLY (SUCTION CONTROL VALVE)

CHECK IF DTC OUTPUT RECURS

CHECK HARNESS AND CONNECTOR (SCV - ECM)

REPLACE COMMON RAIL ASSEMBLY

CHECK IF DTC OUTPUT RECURS (SEE IF DTC P0088 IS OUTPUT AGAIN)

DESCRIPTION

HINT:

1. DTC P0088 and P1229 can be detected if the vehicle is driven at 50 km/h (31 mph) for 5 minutes.
   
2. For more information on the supply pump (suction control valve) and common rail system, refer to the system description (Click here).
   
3. When DTC P0088 and/or P1229 is set, check the internal fuel pressure of the common rail by entering the following menus on the intelligent tester: Powertrain / Engine / Data List / Fuel Press.
   

MONITOR DESCRIPTION

1. P0088 (Internal fuel pressure too high):
   The ECM sets this DTC if the fuel pressure inside the common rail is more than 200 MPa (2,039 kgf/cm², 29,007 psi). This DTC indicates that: 1) the suction control valve may be stuck open, 2) there may be a short in the suction control valve circuit.
   If this DTC is set, the ECM enters fail-safe mode and limits the engine power. The fail-safe mode continues until the engine switch is turned OFF.
   

1. P1229 (Fuel over-feed):
   The ECM sets 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. Under this condition, the pressure discharge valve operates frequently.
   If this DTC is set, the ECM enters fail-safe mode and limits the engine power. The fail-safe mode continues until the engine switch is turned OFF.
   

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

WIRING DIAGRAM

INSPECTION PROCEDURE

NOTICE:

1. After replacing the ECM, the new ECM needs registration (Click here) and initialization (Click here).
   
2. After replacing a supply pump, the ECM needs initialization (Click here).
   

1. Connect the intelligent tester to the DLC3.
   

2. Turn the engine switch ON (IG) and turn the intelligent tester ON.
   

3. Enter the following menus: Powertrain / Engine / DTC.
   

4. Read the DTCs.
   
   

   Result:

   
   

   Display (DTC Output)	Proceed to
   P0088 and/or P1229	A
   P0190, P0192 and/or P0193	B

1. Disconnect the E70 valve connector.
   

2. Measure the resistance of the suction control valve.
   

   Standard resistance:

   Condition	Specified Condition
   20°C (68°F)	1.9 to 2.3 Ω

1. Connect the intelligent tester to the DLC3.
   

2. Turn the engine switch ON (IG) and turn the intelligent tester ON.
   

3. Enter the following menus: Powertrain / Engine / DTC / Clear.
   

4. Disconnect the suction control valve connector and then start the engine. Wait for 1 minute.
   

5. Enter the following menus: Powertrain / Engine / DTC.
   

6. Read the DTCs.
   
   

   Result:

   
   

   Display (DTC Output)	Proceed to
   No output or engine does not start	A
   P1229	B

1. Disconnect the E70 valve connector.
   

2. Disconnect the E59 ECM connector.
   

3. Measure the resistance of the wire harness side connectors.
   

   Standard resistance:

   Tester Connection	Specified Condition
   PCV+ (E70-1) - PCV+ (E59-42)	Below 1 Ω
   PCV- (E70-2) - PCV- (E59-41)	Below 1 Ω
   PCV+ (E70-1) or PCV+ (E59-42) - Body ground	10 kΩ or higher
   PCV- (E70-2) or PCV- (E59-41) - Body ground	10 kΩ or higher

1. Connect the intelligent tester to the DLC3.
   

2. Turn the engine switch ON (IG) and turn the tester ON.
   

3. Clear DTCs.
   

4. Start the engine.
   

5. Enter the following menus: Powertrain / Engine / DTC.
   

6. Read the DTCs using the intelligent tester.
   
   

   Result:

   
   

   Display (DTC output)	Proceed to
   P0088	A
   No output	B