ECD SYSTEM (w/ EGR Cooler), Diagnostic DTC:P1229

DTC Code DTC Name
P1229 Fuel Pump System

DESCRIPTION

Refer to the SYSTEM DESCRIPTION Click here.

DTC No. DTC Detection Condition Trouble Area
P1229

Fuel over-feed:

Fuel pressure is beyond the target fuel pressure despite ECM closing suction control valve

(1 trip detection logic)

  • Short in supply pump (suction control valve) circuit

  • Supply pump (suction control valve)

  • ECM

Tech Tips


  • For more information on the supply pump (suction control valve) and common rail system, refer to the system description Click here.

  • When DTC P1229 is stored, check the internal fuel pressure of the common rail by entering the following menus on the intelligent tester: Powertrain / Engine and ECT / Data List / Fuel Press.

    Reference
    Engine Speed Fuel Pressure
    Idling Approximately 25000 to 35000 kPa
    3000 rpm (No engine load) Approximately 50000 to 70000 kPa

MONITOR DESCRIPTION

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 that there may be a short 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 ignition switch is turned OFF.

MONITOR STRATEGY

P1229:
Required sensor Fuel pressure sensor
Frequency of operation Continuous
Duration 1 minute
MIL operation 1 driving cycle

TYPICAL ENABLING CONDITIONS

P1229:
Item Specification
Target fuel pressure variation Small
The monitor will not run if the fuel pressure sensor, suction control valve circuit, or pressure discharge valve is malfunctioning.

TYPICAL MALFUNCTION THRESHOLDS

P1229:
Detection Criteria Threshold
The fuel pressure of the common rail with the suction control valve closed. Remains higher than targeted fuel pressure
Behavior of the pressure discharge valve Frequently operates

WIRING DIAGRAM

A01E22FE08

INSPECTION PROCEDURE

Tech Tips

Read freeze frame data using the intelligent tester. 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


  1. CHECK OTHER DTC OUTPUT


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch ON and turn the tester ON.

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

    4. Read the DTCs.

      Result
      Display (DTC Output) Proceed to
      P1229 A
      P1229 and other DTCs B

    B

    GO TO DTC CHART

    A

  2. INSPECT SUPPLY PUMP ASSEMBLY (SUCTION CONTROL VALVE)


    1. A01DVR6E03

      Disconnect the S8 suction control valve connector.

    2. Measure the resistance of the suction control valve.

      Standard resistance
      Tester Connection Condition Specified Condition
      1 - 2 20°C (68°F) 1.9 to 2.3 Ω

    NG

    REPLACE SUPPLY PUMP ASSEMBLY (SUCTION CONTROL VALVE) Click here

    OK

  3. CHECK IF DTC OUTPUT RECURS (DTC P1229)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch ON and turn the tester ON.

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

    4. Clear the DTCs.

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

      Tech Tips

      If the engine does not start, the suction control valve is normal. Therefore proceed to procedure 4.

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

    7. Read the DTCs.

      Result
      Display (DTC Output) Proceed to
      P1229 not output A
      P1229 B

    B

    REPLACE SUPPLY PUMP ASSEMBLY (SUCTION CONTROL VALVE) Click here

    A

  4. CHECK HARNESS AND CONNECTOR (SUCTION CONTROL VALVE - ECM [PROCEDURE 4])


    1. A01DWE5E13

      Disconnect the S8 suction control valve connector.

    2. Disconnect the E8 ECM connector.

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

      Standard resistance (Check for open)
      Tester Connection Specified Condition
      S8-1 - PCV+ (E8-2) Below 1 Ω
      S8-2 - PCV- (E8-1)
      Standard resistance (Check for short)
      Tester Connection Specified Condition
      S8-1 or PCV+ (E8-2) - Body ground 10 kΩ or higher
      S8-2 or PCV- (E8-1) - Body ground

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. INSPECT ECM (PCV VOLTAGE)


    1. A01DVT5E21

      Inspect using the oscilloscope.

    2. During cranking or idling, check the waveform between the specified terminals of the E8 ECM connector.

      Standard
      Tester Connection Specified Condition
      PCV+ (E8-2) - PCV- (E8-1) Correct waveform is as shown

    NG

    REPLACE ECM Click here

    OK

  6. CHECK IF DTCS OUTPUT RECUR

    Tech Tips

    After clearing the DTC(s), drive the vehicle at 50 km/h (31 mph) for 5 minutes, and then confirm that DTC P1229 is not present again.


    NEXT

    END