SFI SYSTEM(w/ EGR System), Diagnostic DTC:P0403

DTC Code DTC Name
P0403 Exhaust Gas Recirculation Control Circuit

DESCRIPTION

Refer to DTC P0401.

Click here

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Memory

P0403

Exhaust Gas Recirculation Control Circuit

Both of the following conditions are met: (1 trip detection logic)

  • (a) The engine is running.

  • (b) Any of the terminals EGR1 to EGR4 has a fixed voltage of 0 V.

  • Open or short in EGR valve assembly circuit

  • EGR valve assembly

  • EFI-MAIN relay

  • ECM

Comes on

DTC stored

MONITOR DESCRIPTION

This DTC is stored if an open or short in the EGR valve assembly circuit is detected.

Example:

  • If the EGR1, EGR2, EGR3 or EGR4 terminal output voltage is excessively low, but the step motor is still operating, the ECM determines that there is a short in the EGR valve assembly circuit, and stores this DTC.

  • If the EGR1, EGR2, EGR3 or EGR4 terminal output voltage is excessively low, and the step motor is not operating, the ECM determines that there is an open in the EGR valve assembly circuit, and stores this DTC.

MONITOR STRATEGY

Frequency of Operation

Continuous

CONFIRMATION DRIVING PATTERN

A215251E20

  1. Connect the GTS to the DLC3.

  2. Turn the power switch on (IG) and turn the GTS on.

  3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).

  4. Turn the power switch off and wait for at least 30 seconds.

  5. Turn the power switch on (IG) and turn the GTS on [A].

  6. Put the engine in inspection mode (maintenance mode).

    Click here

  7. Start the engine and warm it up [B].

  8. With the engine running, drive the vehicle at 20 km/h (12 mph) or more for 10 minutes [C].

    CAUTION:

    When performing the confirmation driving pattern, obey all speed limits and traffic laws.

    Tip:

    If the engine stops, further depress the accelerator pedal to restart the engine.

  9. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [D].

  10. Read the pending DTCs.

    Tip:

    • If a pending DTC is output, the system is malfunctioning.

    • If a pending DTC is not output, perform the following procedure.

  11. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

  12. Input the DTC: P0403.

  13. Check the DTC judgment result.

    GTS Display

    Description

    NORMAL

    • DTC judgment completed

    • System normal

    ABNORMAL

    • DTC judgment completed

    • System abnormal

    INCOMPLETE

    • DTC judgment not completed

    • Perform driving pattern after confirming DTC enabling conditions

    N/A

    • Unable to perform DTC judgment

    • Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit
    Tip:

    • If the judgment result shows NORMAL, the system is normal.

    • If the judgment result shows ABNORMAL, the system has a malfunction.

WIRING DIAGRAM

A312550E05

CAUTION / NOTICE / HINT

Note:

Inspect the fuses for circuits related to this system before performing the following procedure.

Tip:

Read freeze frame data using the GTS. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. 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.

PROCEDURE

  1. PERFORM ACTIVE TEST USING GTS (CONTROL THE EGR STEP POSITION)

    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Put the engine in inspection mode (maintenance mode).

      Click here

      Powertrain > Hybrid Control > Utility

      Tester Display

      Inspection Mode

    5. Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.

      Tip:

      The A/C switch and all accessory switches should be off.

    6. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the EGR Step Position / Primary / MAP and Throttle Idle Position.

      Powertrain > Engine and ECT > Active Test

      Active Test Display

      Control the EGR Step Position

      Data List Display

      MAP

      Throttle Idle Position

    7. Confirm that the Throttle Idle Position is ON and check the MAP values in the Data List while performing the Active Test.

      Tip:

      • Do not leave the EGR valve open for 10 seconds or more during the Active Test.

      • Be sure to return the EGR valve to step 0 when the Active Test is completed.

      • Do not open the EGR valve 30 steps or more during the Active Test.

      OK

      MAP change in response to EGR step position when Throttle Idle Position is ON in Data List.

      Standard

      -

      EGR Step Position (Active Test)

      0 Steps

      0 to 30 Steps

      MAP

      (Data List)

      (EGR valve is fully closed)

      MAP value is at least +10 kPa (75 mmHg) higher than when EGR valve is fully closed
      Tip:

      • While performing the Active Test, if the increase in the value of MAP is small, the EGR valve assembly may be a malfunctioning.

      • Even if the EGR valve assembly is malfunctioning, rough idling or an increase in the value of MAP may occur while performing the Active Test. However, the amount that the value of MAP increases will be smaller than normal.

    Result

    Proceed to

    OK

    NG
    OK

    CHECK FOR INTERMITTENT PROBLEMS

    Click here

    NG

  2. INSPECT EGR VALVE ASSEMBLY

    1. Inspect the EGR valve assembly.

      Click here

      Tip:

      Perform "Inspection After Repair" after replacing the EGR valve assembly.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE EGR VALVE ASSEMBLY

    Click here

    OK

  3. CHECK TERMINAL VOLTAGE (POWER SOURCE OF EGR VALVE ASSEMBLY)

    1. A217947C09

      *a

      Front view of wire harness connector

      (to EGR Valve Assembly)

      Disconnect the EGR valve assembly connector.

    2. Turn the power switch on (IG).

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

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      B57-2 (+B1) - Body ground

      Power switch on (IG)

      11 to 14 V

      B57-5 (+B2) - Body ground

      Power switch on (IG)

      11 to 14 V

    Result

    Result

    OK

    NG
    NG

    CHECK HARNESS AND CONNECTOR (EFI-MAIN RELAY - EGR VALVE ASSEMBLY)Click here

    OK

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

    1. Disconnect the EGR 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

      B57-4 (EGR1) - B75-28 (EGR1)

      Always

      Below 1 Ω

      B57-3 (EGR2) - B75-27 (EGR2)

      Always

      Below 1 Ω

      B57-6 (EGR3) - B75-26 (EGR3)

      Always

      Below 1 Ω

      B57-1 (EGR4) - B75-25 (EGR4)

      Always

      Below 1 Ω

      B57-4 (EGR1) or B75-28 (EGR1) - Body ground and other terminals

      Always

      10 kΩ or higher

      B57-3 (EGR2) or B75-27 (EGR2) - Body ground and other terminals

      Always

      10 kΩ or higher

      B57-6 (EGR3) or B75-26 (EGR3) - Body ground and other terminals

      Always

      10 kΩ or higher

      B57-1 (EGR4) or B75-25 (EGR4) - Body ground and other terminals

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    OK

    REPLACE ECM

    Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  5. CHECK HARNESS AND CONNECTOR (EFI-MAIN RELAY - EGR VALVE ASSEMBLY)

    1. Disconnect the EGR valve assembly connector.

    2. Remove the EFI-MAIN relay from the engine room relay block and junction block assembly.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      3 (EFI-MAIN relay) - B75-2 (+B1)

      Always

      Below 1 Ω

      3 (EFI-MAIN relay) - B75-5 (+B2)

      Always

      Below 1 Ω

      3 (EFI-MAIN relay) or B75-2 (+B1) - Body ground and other terminals

      Always

      10 kΩ or higher

      3 (EFI-MAIN relay) or B75-5 (+B2) - Body ground and other terminals

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    OK

    GO TO ECM POWER SOURCE CIRCUIT

    Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR