DTC    P0405    Exhaust Gas Recirculation Sensor "A" Circuit Low

DTC    P0406    Exhaust Gas Recirculation Sensor "A" Circuit High

for Preparation Click here


DESCRIPTION

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 gas is taken out from exhaust port to EGR valve, and when the valve opens, it is circulated into the intake manifold by difference of the pressure between exhaust manifold and intake manifold.
The ECM judges engine condition from engine speed (NE) and injection amount and operate 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, EGR system operates the amount of EGR gas depend on various environment.
Adopting the 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.

P0405 
DTC Detection Drive Pattern
DTC Detection Condition
Trouble Area
Ignition switch ON for 3 seconds
Open or short in EGR valve position sensor circuit
(1 trip detection logic)
  1. Electric EGR valve assembly
  2. Open or short in EGR valve position sensor circuit
  3. ECM

P0406 
DTC Detection Drive Pattern
DTC Detection Condition
Trouble Area
Ignition switch ON for 3 seconds
Open or short in EGR valve position sensor circuit
(1 trip detection logic)
  1. Electric EGR valve assembly
  2. Open or short in EGR valve position sensor circuit
  3. ECM

WIRING DIAGRAM


A198996E02


INSPECTION PROCEDURE

NOTICE:
When replacing the ECM, the ECM needs Registration and Initialization (Click here).

HINT:
When the ECM must be replaced, before replacing the ECM, perform the "Learning Values Save" function using the intelligent tester. Then after installing the new ECM, perform all of the initializations/registrations for the "Learning Values Write" function by following the instructions shown on the tester display.

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


    A200328E01

  1. Disconnect the electric EGR valve assembly connector.

  1. Disconnect the ECM connector.

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

    Standard Resistance (Check for Open):
    Tester Connection
    		Condition
    		Specified Condition
    B50-5 (VC) - B9-26 (VCEG)
    		Always
    		Below 1 Ω
    B50-4 (VTA) - B9-27 (EGLS)
    		Always
    		Below 1 Ω
    B50-3 (E2) - B9-25 (EEGL)
    		Always
    		Below 1 Ω

    Standard Resistance (Check for Short):
    Tester Connection
    		Condition
    		Specified Condition
    B50-5 (VC) or B9-26 (VCEG) - Body ground
    		Always
    		10 kΩ or higher
    B50-4 (VTA) or B9-27 (EGLS) - Body ground
    		Always
    		10 kΩ or higher
    B50-3 (E2) or B9-25 (EEGL) - Body ground
    		Always
    		10 kΩ or higher

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to electric EGR Valve Assembly)
    *2
    		Front view of wire harness connector
    (to ECM)

  1. Reconnect the electric EGR valve assembly connector.

  1. Reconnect the ECM connector.



NG
Go to step 4
OK


2.CHECK ECM TERMINAL VOLTAGE (VC TERMINAL)


    A200329E01

  1. Disconnect the electric EGR valve assembly connector.

  1. Turn the ignition switch to ON.

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

    Standard Voltage:
    Tester Connection
    		Switch Condition
    		Specified Condition
    B50-5 (VC) - B50-3 (E2)
    		Ignition switch ON
    		4.5 to 5.5 V

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Electric EGR Valve Assembly)

  1. Reconnect the electric EGR valve assembly connector.



NG
Go to step 6
OK


3.REPLACE ELECTRIC EGR CONTROL VALVE ASSEMBLY

  1. Replace electric EGR valve assembly (Click here).

  1. Turn the ignition switch to ON.

  1. Turn the ignition switch off and wait for 30 seconds or more.



NEXT
Go to step 5

4.REPAIR OR REPLACE HARNESS OR CONNECTOR

NEXT


5.CHECK WHETHER DTC OUTPUT RECURS (DTC P0405 OR P0406)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to ON and turn the tester on.

  1. Clear the DTCs (Click here).

  1. Turn the ignition switch to ON and wait for 15 seconds or more.

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

  1. Read the DTCs.
    Result 
    Result
    		Proceed to
    No DTC output
    		A
    DTC P0405 or P0406
    		B



B
Go to step 6
A

END 

6.REPLACE ECM

  1. Replace the ECM (Click here).


NEXT


7.CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

  1. Connect the intelligent tester to the DLC3.

  1. Clear the DTCs (Click here).

  1. Turn the ignition switch to ON and wait for 15 seconds or more.

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

  1. Confirm that the DTC is not output again.


NEXT

END