СИСТЕМА ECD, Diagnostic DTC:P0405, P0406

DTC Code DTC Name
P0405 Exhaust Gas Recirculation Sensor "A" Circuit Low
P0406 Exhaust Gas Recirculation Sensor "A" Circuit High

DESCRIPTION

The EGR system is designed to reduce and control NOx formation due to a reduction of peak temperature in the engine combustion chamber, which is accomplished by introducing an inert gas into intake manifold.

Exhaust gases are redirected to the EGR valve, and when the valve opens, the gases are circulated into the intake manifold by difference in the pressure between exhaust manifold and intake manifold.

The ECM judges engine condition from engine speed (NE) and injection amount and operates the EGR valve with DC motor and the amount of EGR gas. And also, it controls diesel throttle opening position with DC motor. By sensing the engine coolant temperature sensor and atmospheric sensor, the EGR system can operate according to various driving conditions.

Adopting an exhaust gas passage in the cylinder head and a water cooling type EGR cooler makes it possible to lower the temperature of the exhaust gas and recirculate a great amount of exhaust gas.

DTC No. Detection Item DTC Detection Condition Trouble Area MIL Memory
P0405 Exhaust Gas Recirculation Sensor "A" Circuit Low

Open or short in EGR valve position sensor circuit

(2 trip detection logic)

  • Electric EGR control valve assembly

  • Open or short in EGR valve position sensor circuit

  • ECM

Comes on DTC stored
P0406 Exhaust Gas Recirculation Sensor "A" Circuit High

Open or short in EGR valve position sensor circuit

(2 trip detection logic)

  • Electric EGR control valve assembly

  • Open or short in EGR valve position sensor circuit

  • ECM

Comes on DTC stored
Table 1. DTC Detection Drive Pattern
DTC No. DTC Detection Drive Pattern
P0405 Ignition switch ON for 3 seconds
P0406

WIRING DIAGRAM

A012MB8E01
Table 2.
*a (Shielded)
*b Electric EGR Control Valve Assembly

CAUTION / NOTICE / HINT

Note:

When replacing the ECM, perform ECM Initialization and Registration.

Click here Нажмите здесь

Tip:
  • When the ECM must be replaced, before replacing the ECM, perform the "Learning Values Save" function using the GTS. Then after installing a new ECM, perform all of the initialization and registration procedures for the "Learning Values Write" function by following the instructions shown on the GTS display.

  • 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

  1. CHECK HARNESS AND CONNECTOR (ELECTRIC EGR CONTROL VALVE ASSEMBLY - ECM)

    1. Disconnect the electric EGR control valve assembly connector.

    2. Disconnect the ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      B134-5 (VC) - B138-26 (VCEG) Always Below 1 Ω
      B134-4 (VTA) - B138-27 (EGLS) Always Below 1 Ω
      B134-3 (E2) - B138-25 (EEGL) Always Below 1 Ω
      B134-5 (VC) or B138-26 (VCEG) - Body ground Always 10 kΩ or higher
      B134-4 (VTA) or B138-27 (EGLS) - Body ground Always 10 kΩ or higher
      B134-3 (E2) or B138-25 (EEGL) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG
    NG Нажмите здесь

    OK
  2. CHECK TERMINAL VOLTAGE (VC VOLTAGE)

    A012INOC02
    *a

    Front view of wire harness connector

    (to Electric EGR Control Valve Assembly)

    1. Disconnect the electric EGR control valve assembly connector.

    2. Turn the ignition switch to ON.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      B134-5 (VC) - B134-3 (E2) Ignition switch ON 4.5 to 5.5 V
      Result
      Proceed to
      OK
      NG
    NG Нажмите здесь

    GO TO STEP 5


    OK
  3. REPLACE ELECTRIC EGR CONTROL VALVE ASSEMBLY

    1. Replace the electric EGR control valve assembly.

      Click hereНажмите здесь

      Result
      Proceed to
      NEXT
    NEXT
  4. CHECK WHETHER DTC OUTPUT RECURS (DTC P0405 OR P0406)

    1. Connect the GTS to the DLC3.

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

    3. Clear the DTCs.

      Powertrain > Engine and ECT > Clear DTCs
    4. Turn the ignition switch to ON and wait for 15 seconds or more.

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

    6. Read the pending DTCs.

      Powertrain > Engine and ECT > Trouble Codes
      Result
      ResultProceed to
      DTC is not outputA
      DTC P0405 or P0406 is outputB
    A

    END


    B
  5. REPLACE ECM

    1. Replace the ECM.

      Click hereНажмите здесь

      Result
      Proceed to
      NEXT
    NEXT
  6. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

    1. Connect the GTS to the DLC3.

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

    3. Clear the DTCs.

      Powertrain > Engine and ECT > Clear DTCs
    4. Turn the ignition switch to ON and wait for 15 seconds or more.

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

    6. Confirm that the pending DTC is not output again.

      Powertrain > Engine and ECT > Trouble Codes
      Result
      Proceed to
      NEXT
    NEXT

    END


  7. REPAIR OR REPLACE HARNESS OR CONNECTOR

    Result
    Proceed to
    NEXT
    NEXT Нажмите здесь

    GO TO STEP 4