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Home >> Lexus >> 2023 >> NX 250 AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 123 (Engine Control System - Diagnostic Codes (P22AB-U115C) & Circuit Tests (1 Of 2)) >> SFI System >> DTC P25B3-72: Turbocharger/Supercharger Wastegate "A" Actuator Stuck Open [11/2021 - 03/2023] >> Procedure

DTC P25B3-72: Turbocharger/Supercharger Wastegate "A" Actuator Stuck Open [11/2021 - 03/2023]: Procedure

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  1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P25B3-72) 
    1. Read the DTCs.

      Powertrain > Engine > Trouble Codes 

      Result

      Result Proceed to
      DTC P25B3-72 is output A
      DTC P25B3-72 and other DTCs are output B

      HINT: 

      If any DTCs other than P25B3-72 are output, troubleshoot those DTCs first.

    Result: 

    B 

    GO TO DTC CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART [11/2021 - 03/2023] 

    Result: 

    A 

    See step  2

  2. PERFORM ACTIVE TEST USING GTS (CONTROL THE WASTEGATE VALVE DUTY RATIO) 
    1. Start the engine.
    2. Perform the Active Test. Check that the waste gate valve is operating.

      Powertrain > Engine > Active Test 

      Tester Display
      Control the Wastegate Valve Duty Ratio

      OK

      The waste gate valve is operating.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  15

    Result: 

    OK 

    See step  3

  3. INSPECT MASS AIR FLOW METER SUB-ASSEMBLY 
    1. Inspect the mass air flow meter sub-assembly, referring to On-vehicle Inspection for Mass Air Flow Meter.

      Refer to ON-VEHICLE INSPECTION [11/2021 - ]

    2. Inspect the mass air flow meter sub-assembly, referring to Inspection for Mass Air Flow Meter.

      Refer to INSPECTION [11/2021 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  12

    Result: 

    OK 

    See step  4

  4. INSPECT NO. 2 TURBO PRESSURE SENSOR 
    1. Inspect the No. 2 turbo pressure sensor.

      Refer to PROCEDURE - Step 1

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  7

    Result: 

    OK 

    See step  5

  5. CHECK WHETHER DTC OUTPUT RECURS (DTC P25B3-72) 
    1. Connect the GTS to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the GTS on.
    4. Clear the DTCs.

      Powertrain > Engine > Clear DTCs 

    5. Turn the ignition switch off and wait for at least 30 seconds.
    6. Start the engine and warm it up.
    7. Turn the GTS on.
    8. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
    9. Check the DTC judgment result.

      Powertrain > Engine > Utility 

      Tester Display
      All Readiness
    10. Input the DTC: P25B3-72.

      Result

      Result Proceed to
      NORMAL
      (DTCs are not output)      		 A
      ABNORMAL
      (DTC P25B3-72 is output)      		 B

    Result: 

    A 

    CHECK FOR INTERMITTENT PROBLEMS. Refer to  CHECK FOR INTERMITTENT PROBLEMS [11/2021 - ] 

    Result: 

    B 

    See step  6

  6. REPLACE ECM 
    1. Replace the ECM.

      Refer to REMOVAL [11/2021 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  24

  7. CHECK TERMINAL VOLTAGE (POWER SOURCE OF NO. 2 TURBO PRESSURE SENSOR) 
    1. Disconnect the No. 2 turbo pressure sensor 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
      B72-3 (VC) - B72-2 (E2) Ignition switch ON 4.5 to 5.5 V
      B72-1 (PTA) - B72-2 (E2) Ignition switch ON 3.0 to 5.0 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  9

    Result: 

    OK 

    See step  8

  8. REPLACE NO. 2 TURBO PRESSURE SENSOR 
    1. Replace the No. 2 turbo pressure sensor.

      Refer to PROCEDURE - Step 3

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  24

  9. CHECK HARNESS AND CONNECTOR (NO. 2 TURBO PRESSURE SENSOR - ECM) 
    1. Disconnect the No. 2 turbo pressure sensor 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
      B72-3 (VC) - B49-102 (VPTA) Always Below 1 Ω
      B72-1 (PTA) - B49-126 (PTA) Always Below 1 Ω
      B72-2 (E2) - B49-125 (EPTA) Always Below 1 Ω
      B72-3 (VC) or B49-102 (VPTA) - Body ground and other terminals Always 10 kΩ or higher
      B72-1 (PTA) or B49-126 (PTA) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  11

    Result: 

    OK 

    See step  10

  10. REPLACE ECM 
    1. Replace the ECM.

      Refer to REMOVAL [11/2021 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  24

  11. REPAIR OR REPLACE HARNESS OR CONNECTOR 
    1. Repair or replace the wire harness or connector.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  24

  12. CHECK TERMINAL VOLTAGE (POWER SOURCE OF MASS AIR FLOW METER SUB-ASSEMBLY) 
    1. Disconnect the mass air flow meter sub-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
      B20-3 (VCC) - B20-2 (E2G) Ignition switch ON 4.8 to 5.2 V
      B20-1 (FG) - B20-2 (E2G) Ignition switch ON 4.8 to 5.2 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  14

    Result: 

    OK 

    See step  13

  13. INSPECT MASS AIR FLOW METER SUB-ASSEMBLY 
    1. Inspect the mass air flow meter sub-assembly.

      Refer to ON-VEHICLE INSPECTION [11/2021 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ECM. Refer to  REMOVAL [11/2021 - ] 

    Result: 

    NG 

    REPLACE MASS AIR FLOW METER SUB-ASSEMBLY. Refer to  REMOVAL [11/2021 - ] 

  14. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER SUB-ASSEMBLY - ECM) 
    1. Disconnect the mass air flow meter sub-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
      B20-3 (VCC) - B49-73 (VCVG) Always Below 1 Ω
      B20-1 (FG) - B49-75 (VG) Always Below 1 Ω
      B20-2 (E2G) - B49-74 (E2G) Always Below 1 Ω
      B20-3 (VCC) or B49-73 (VCVG) - Body ground and other terminals Always 10 kΩ or higher
      B20-1 (FG) or B49-75 (VG) - Body ground and other terminals Always 10 kΩ or higher
      B20-2 (E2G) or B49-74 (E2G) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ECM. Refer to  REMOVAL [11/2021 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  15. PERFORM ACTIVE TEST USING GTS (CONTROL THE WASTEGATE VALVE DUTY RATIO) 
    GTY1129654Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *1 Vacuum Regulating Valve Assembly
    *2 Vacuum Gauge
    1. Disconnect the vacuum hose (waste gate valve actuator with bracket assembly side) of the vacuum regulating valve assembly.
    2. When the waste gate valve is operated using the GTS and a vacuum gauge, check the vacuum of the vacuum regulating valve assembly.
    3. Start the engine.
    4. Perform the Active Test using the GTS.

      Powertrain > Engine > Active Test 

      Tester Display
      Control the Wastegate Valve Duty Ratio

      OK

      GTS Operation Specified Condition
      100% Higher than 40 kPa (300 mmHg, 11.8 in. Hg)
      0% Less than 10 kPa (75 mmHg, 3.0 in. Hg)

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  17

    Result: 

    OK 

    See step  16

  16. REPLACE TURBOCHARGER SUB-ASSEMBLY 
    1. Replace the turbocharger sub-assembly.

      Refer to REMOVAL [11/2021 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  24

  17. CHECK VACUUM PUMP ASSEMBLY 
    GTY1079250Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *1 Vacuum Regulating Valve Assembly
    1. Disconnect the vacuum hose (vacuum pump assembly side) of the vacuum regulating valve assembly.
    2. Start the engine.
    3. Check whether the vacuum hose of the vacuum regulating valve assembly applies suction your finger.

      OK

      Vacuum hose applies suction to finger.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  21

    Result: 

    OK 

    See step  18

  18. INSPECT VACUUM REGULATING VALVE ASSEMBLY 
    1. Inspect the vacuum regulating valve assembly.

      Refer to INSPECTION [11/2021 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  20

    Result: 

    OK 

    See step  19

  19. REPAIR OR REPLACE VACUUM HOSE (WASTE GATE VALVE ACTUATOR WITH BRACKET ASSEMBLY - VACUUM REGULATING VALVE ASSEMBLY) 
    1. repair or replace the vacuum hose (waste gate valve actuator with bracket assembly - vacuum regulating valve assembly)

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  24

  20. REPLACE VACUUM REGULATING VALVE ASSEMBLY 
    1. Replace the vacuum regulating valve assembly.

      Refer to REMOVAL [11/2021 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  24

  21. INSPECT VACUUM PUMP ASSEMBLY 
    1. Inspect the vacuum pump assembly.

      Refer to ON-VEHICLE INSPECTION [11/2021 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  23

    Result: 

    OK 

    See step  22

  22. REPAIR OR REPLACE VACUUM LINE (VACUUM REGULATING VALVE ASSEMBLY - VACUUM PUMP ASSEMBLY) 
    1. repair or replace the vacuum line (vacuum regulating valve assembly - vacuum pump assembly).

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  24

  23. REPLACE VACUUM PUMP ASSEMBLY 
    1. Replace the vacuum pump assembly.

      Refer to REMOVAL [11/2021 - 03/2023]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  24

  24. CHECK WHETHER DTC OUTPUT RECURS (DTC P25B3-72) 
    1. Clear the DTCs.

      Powertrain > Engine > Clear DTCs 

    2. Turn the ignition switch off and wait for at least 30 seconds.
    3. Start the engine and warm it up.
    4. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
    5. Check the DTC judgment result.

      Powertrain > Engine > Utility 

      Tester Display
      All Readiness
    6. Input the DTC: P25B3-72.
      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

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    END 

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