SFI SYSTEM, Diagnostic DTC:P1235, P1236

DTC Code DTC Name
P1235 High Pressure Fuel Pump Circuit
P1236 High Pressure Fuel Pump No. 2 Circuit

DESCRIPTION

The fuel pump (for high pressure) has a plunger and a spill control valve. The plunger reciprocates by the camshaft rotation and pumps the fuel into the direct fuel injectors. The spill control valve regulates the fuel flow from the fuel tank to the plunger. When the spill control valve opens (ON), the fuel pressure rises. The injector driver operates the spill control valve using DC 50 V. The engine control module (ECM) controls the injector driver to maintain the fuel pressure at 4 to 13 MPa (41 to 133 kgf/cm2, 574 to 1857 psi).

DTC No. DTC Detection Condition Trouble Area
P1235

Open or short in fuel pump (for High Pressure of Bank 1) circuit for 1 second or more

(1 trip detection logic)

  • Open in fuel pump (for High Pressure of Bank 1) circuit

  • Fuel pump (for High Pressure of Bank 1)

  • No. 1 Injector driver

  • ECM
P1236

Open or short in fuel pump (for High Pressure of Bank 2) circuit for 1 second or more

(1 trip detection logic)

  • Open in fuel pump (for High Pressure of Bank 2) circuit

  • Fuel pump (for High Pressure of Bank 2)

  • No. 2 Injector driver

  • ECM

MONITOR DESCRIPTION

The injector driver has the integrated circuit (IC) which monitors the electrical circuit between the spill control valve and injector driver. If an open circuit is detected, the IC sends the malfunction signal (FPD, FPD2) to the ECM. Then, the ECM illuminates the malfunction indicator lamp (MIL) and sets a DTC immediately.

WIRING DIAGRAM

A01GY3GE21

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, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

  • When viewed from the rear of the engine assembly, Bank 1 is on the left side and Bank 2 is on the right side.

PROCEDURE


  1. CHECK DTC


    1. A01GZ6AE03

      Interchange the No. 1 and No. 2 injector driver Click here.

      Note

      Do not disconnect and reconnect the connectors with the power switch on (IG), as the injector driver (EDU) may be damaged.

    2. Connect the intelligent tester to the DLC3.

    3. Turn the power switch on (IG) and turn the tester ON.

    4. Clear DTCs Click here.

      Note

      Before clearing the DTCs, write them down.

    5. Turn the power switch on (READY).

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

    7. Read the DTC.

      Result
      Display (DTC Output) Proceed to
      DTCs do not change A
      DTCs change (change in malfunctioning cylinder or EDU code) B

    B

    REPLACE INJECTOR DRIVER Click here

    A

  2. INSPECT SPILL CONTROL VALVE


    1. A01H2A0E01

      Disconnect the E43 or E35 spill control valve connector.

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

      Standard resistance
      Tester Connection Condition Specified Condition
      1 - 2 20°C (68°F) 1.19 to 1.39 Ω

    NG

    REPLACE FUEL PUMP (for High Pressure) Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (INJECTOR DRIVER - SPILL CONTROL VALVE)


    1. A01GXDGE03

      Disconnect the E16 or E28 injector driver (EDU) connector.

    2. Disconnect the E43 or E35 spill control valve connector.

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

      Standard resistance (Check for open)
      Tester Connection Condition Specified Condition
      E16-1 (FP+) - E43-1 Always Below 54 mΩ
      E16-4 (FP-) - E43-2 Always Below 54 mΩ
      E28-1 (FP2+) - E35-1 Always Below 54 mΩ
      E28-4 (FP2-) - E35-2 Always Below 54 mΩ
      Standard resistance (Check for short)
      Tester Connection Condition Specified Condition
      E16-1 (FP+) or E43-1 - Engine ground Always 1 MΩ or more
      E16-4 (FP-) or E43-2 - Engine ground Always 1 MΩ or more
      E28-1 (FP2+) or E35-1 - Engine ground Always 1 MΩ or more
      E28-4 (FP2-) or E35-2 - Engine ground Always 1 MΩ or more

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK HARNESS AND CONNECTOR (INJECTOR DRIVER - ECM)


    1. A01GZY2E11

      Disconnect the E15 or E27 injector driver connector.

    2. Disconnect the E4 ECM connector.

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

      Standard resistance (Check for open)
      Tester Connection Condition Specified Condition
      E15-8 (FPD) - E4-11 (FPD) Always Below 1 Ω
      E15-7 (FPF1) - E4-10 (FPF1) Always Below 1 Ω
      E27-8 (FPD2) - E4-13 (FPD2) Always Below 1 Ω
      E27-7 (FPF2) - E4-12 (FPF2) Always Below 1 Ω
      Standard resistance (Check for short)
      Tester Connection Condition Specified Condition
      E15-8 (FPD) or E4-11 (FPD) - Body ground Always 10 kΩ or higher
      E15-7 (FPF1) or E4-10 (FPF1) - Body ground Always 10 kΩ or higher
      E27-8 (FPD2) or E4-13 (FPD2) - Body ground Always 10 kΩ or higher
      E27-7 (FPF2) or E4-12 (FPF2) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE ECM Click here