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Home >> Lexus >> 2017 >> RX 450h Base >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (Diagnostic Codes) (4 Of 8) >> SFI System >> DTC P0403: Exhaust Gas Recirculation Circuit [10/2015 - 07/2020] >> Procedure
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DTC P0403: Exhaust Gas Recirculation Circuit [10/2015 - 07/2020]: Procedure

  1. PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE EGR STEP POSITION) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Put the engine in inspection mode (maintenance mode).

      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.

      HINT: 

      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 / Data List / 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 value in the Data List while performing the Active Test.

      HINT: 

      • 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 (1.45 psi) higher than when EGR valve is fully closed

      HINT: 

      • 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

    Result: 

    OK 

    CHECK FOR INTERMITTENT PROBLEMS. Refer to  CHECK FOR INTERMITTENT PROBLEMS [10/2015 - ] 

    Result: 

    NG 

    See step  2

  2. INSPECT EGR VALVE ASSEMBLY 
    1. Inspect the EGR valve assembly.

      Refer to INSPECTION [10/2015 - ]

      HINT: 

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

      Refer to INITIALIZATION [10/2015 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE EGR VALVE ASSEMBLY. Refer to  REMOVAL [10/2015 - ] 

    Result: 

    OK 

    See step  3

  3. CHECK TERMINAL VOLTAGE (POWER SOURCE OF EGR VALVE ASSEMBLY) 
    1. Disconnect the EGR valve assembly connector.
      GTY644159Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector (to EGR Valve Assembly)
    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
      D66-2 (+B1) - Body ground Power switch on (IG) 11 to 14 V
      D66-5 (+B2) - Body ground Power switch on (IG) 11 to 14 V

      Result

      Result
      OK
      NG

    Result: 

    NG 

    See step  5

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (EGR VALVE ASSEMBLY - ECM ASSEMBLY) 
    1. Disconnect the EGR valve assembly connector.
    2. Disconnect the ECM assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      D66-4 (EGR1) - D1-11 (EGR1) Always Below 1 Ω
      D66-3 (EGR2) - D1-10 (EGR2) Always Below 1 Ω
      D66-6 (EGR3) - D1-9 (EGR3) Always Below 1 Ω
      D66-1 (EGR4) - D1-12 (EGR4) Always Below 1 Ω
      D66-4 (EGR1) or D1-11 (EGR1) - Body ground and other terminals Always 10 kΩ or higher
      D66-3 (EGR2) or D1-10 (EGR2) - Body ground and other terminals Always 10 kΩ or higher
      D66-6 (EGR3) or D1-9 (EGR3) - Body ground and other terminals Always 10 kΩ or higher
      D66-1 (EGR4) or D1-12 (EGR4) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ECM ASSEMBLY. Refer to  REMOVAL [10/2015 - 08/2016]  , or refer to  REMOVAL [08/2016 - 03/2018]  , or refer to  REMOVAL [03/2018 - 08/2019]  , or refer to  REMOVAL [08/2019 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  5. CHECK HARNESS AND CONNECTOR (SEMICONDUCTOR PWR INTEGRATION ECU - EGR VALVE ASSEMBLY) 
    1. Disconnect the semiconductor pwr integration ECU connector.
    2. Disconnect the EGR valve assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1G-1 - D66-2 (+B1) Always Below 1 Ω
      1G-1 - D66-5 (+B2) Always Below 1 Ω
      1G-1 or D66-2 (+B1) - Body ground and other terminals Always 10 kΩ or higher
      1G-1 or D66-5 (+B2) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE SEMICONDUCTOR POWER INTEGRATION ECU. Refer to  REMOVAL [10/2015 - 08/2016]  , or refer to  REMOVAL [08/2016 - 03/2018]  , or refer to  REMOVAL [03/2018 - 08/2019]  , or refer to  REMOVAL [08/2019 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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