ECD SYSTEM (w/o EGR Cooler Bypass Valve), Diagnostic DTC:P1264

DTC Code DTC Name
P1264 VN Turbo Controller Malfunction

DESCRIPTION

The turbocharger system is comprised of the Variable Nozzle (VN) type turbocharger, the turbo motor driver and the ECM.

The turbocharger has nozzle vane which opens and closes to control the volume of the exhaust gas flowing into the turbine. This, in turn, controls the boost pressure, when the nozzle vane moves towards the closing direction, the pressure increases. When the vane moves towards the opening direction, the pressure decreases.

The turbocharger actuator built on the compressor housing activates the nozzle vane. The nozzle vane position sensor built on the actuator detects the opening angle of nozzle vane. The turbo motor driver receives an opening angle request from the ECM and nozzle vane position sensor signal. Based on these signals, the turbo motor driver operates the DC motor and controls the turbocharger opening angle. The turbo motor driver sends the status as a turbo driver status signal to the ECM.

The ECM sends a opening angle request signal to the turbo motor driver to obtain the nozzle vane position for the optimal boost pressure in accordance with the driving conditions.

A01KF7SE01
DTC No. DTC Detection Condition Trouble Area
P1264

When communication error occurs between turbo motor and ECM

(1 trip detection logic)

  • Turbo motor driver

  • Open or short in turbo motor driver circuit

  • Turbo motor driver ground problem

  • ECM

WIRING DIAGRAM

A01KEQPE01

INSPECTION PROCEDURE

Tech Tips

Read freeze frame data using the intelligent tester. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, freeze frame data can help determine if the vehicle was running or stopped, if the engine was warmed up or not, and other data from the time the malfunction occurred.

Note

If the ECM is replaced, the new ECM needs initialization Click here

PROCEDURE


  1. INSPECT TURBO MOTOR DRIVER


    1. A01KHKLE21
      Text in Illustration
      *1 Turbo Motor Driver Connector
      *a Wire Harness Side
      *b Front View

      Disconnect the T10 turbo motor driver connector.

    2. Turn the ignition switch ON.

    3. Measure the voltage between the specified terminals of the turbo motor driver connector.

      Standard voltage
      Tester Connection Specified Condition
      T10-3 (+B) - T10-4 (GND) 11 to 14 V

    4. Reconnect the turbo motor driver connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. CHECK HARNESS AND CONNECTOR (TURBO MOTOR DRIVER - ECM)


    1. A01KED5E17
      Text in Illustration
      *1 ECM Connector
      *2 Turbo Motor Driver Connector
      *a Front View
      *b Wire Harness Side

      Disconnect the E6 ECM connector.

    2. Disconnect the T10 turbo motor driver connector.

    3. Check the resistance.

      Standard resistance (Check for open)
      Tester Connections Specified Conditions
      E6-10 (VNTO) - T10-7 (VNTO) Below 1 Ω
      E6-17 (VNT1) - T10-2 (VNT1) Below 1 Ω
      Standard resistance (Check for short)
      Tester Connections Specified Conditions
      E6-10 (VNTO) or T10-7 (VNTO) - Body ground 10 kΩ or higher
      E6-17 (VNT1) or T10-2 (VNT1) - Body ground 10 kΩ or higher

    4. Reconnect the turbo motor driver connector.

    5. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. INSPECT ECM (TURBO MOTOR DRIVER - ECM)


    1. A01KEN3E21
      Text in Illustration
      *1 ECM Connector

      While idling the engine, check the waveform of the ECM connectors using an oscilloscope.

      Standard voltage
      Tester Connections Specified Conditions
      E6-10 (VNTO) - E5-7 (E1) Correct waveform is as shown

    NG

    REPLACE ECM

    OK

  4. INSPECT TURBO MOTOR DRIVER (VNT1 VOLTAGE)


    1. A01KEYOE03
      Text in Illustration
      *1 ECM Connector

      While idling the engine, check the waveform of the ECM connectors using an oscilloscope.

      Standard voltage
      Tester Connections Specified Conditions
      E6-17 (VNTI) - E5-7 (E1) Correct waveform is as shown

    NG

    REPLACE TURBO MOTOR DRIVER

    OK

    CHECK FOR INTERMITTENT PROBLEMS Click here