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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 P25B4-73: Turbocharger/Supercharger Wastegate "A" Actuator Stuck Closed [11/2021 - ] >> Procedure

DTC P25B4-73: Turbocharger/Supercharger Wastegate "A" Actuator Stuck Closed [11/2021 - ]: Procedure

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  1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P25B4-73) 
    1. Read the DTCs.

      Powertrain > Engine > Trouble Codes 

      Result

      Result Proceed to
      DTC P25B4-73 is output A
      DTC P25B4-73 and other DTCs are output B

      HINT: 

      If any DTCs other than P25B4-73 are output, troubleshoot those DTCs first.

    Result: 

    B 

    GO TO DTC CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART [11/2021 - 03/2023]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [03/2023 - 03/2024]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [03/2024 - ] 

    Result: 

    A 

    See step  2

  2. CHECK VACUUM REGULATING VALVE ASSEMBLY 
    GTY1077159Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *1 Waste Gate Valve Actuator with Bracket Assembly
    1. Disconnect the vacuum hose of the waste gate valve actuator with bracket assembly.
    2. Start the engine.
    3. Check whether the vacuum hose of the vacuum regulating valve assembly applies no suction your finger.

      OK

      Vacuum hose applies no suction to finger.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  18

    Result: 

    OK 

    See step  3

  3. INSPECT TURBOCHARGER SUB-ASSEMBLY (WASTE GATE VALVE) 
    1. Inspect the waste gate valve.

      Refer to INSPECTION [11/2021 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE TURBOCHARGER SUB-ASSEMBLY. Refer to  REMOVAL [11/2021 - ] 

    Result: 

    OK 

    See step  4

  4. INSPECT TURBOCHARGER SUB-ASSEMBLY (WASTE GATE VALVE ACTUATOR) 
    1. Inspect the waste gate valve actuator.

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

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE TURBOCHARGER SUB-ASSEMBLY. Refer to  REMOVAL [11/2021 - ] 

    Result: 

    OK 

    See step  5

  5. 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  15

    Result: 

    OK 

    See step  6

  6. 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  10

    Result: 

    OK 

    See step  7

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

      Refer to REMOVAL [11/2021 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  8

  8. CHECK WHETHER DTC OUTPUT RECURS (DTC P25B4-73) 
    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: P25B4-73.

      Result

      Result Proceed to
      NORMAL
      (DTCs are not output)      		 A
      ABNORMAL
      (DTC P25B4-73 is output)      		 B

    Result: 

    A 

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

    Result: 

    B 

    See step  9

  9. REPLACE ECM 
    1. Replace the ECM.

      Refer to REMOVAL [11/2021 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  19

  10. 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  12

    Result: 

    OK 

    See step  11

  11. 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  19

  12. 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
      B72-2 (E2) - B49-125 (EPTA) Always Below 1 Ω
      B72-1 (PTA) - B49-126 (PTA) 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  14

    Result: 

    OK 

    See step  13

  13. REPLACE ECM 
    1. Replace the ECM.

      Refer to REMOVAL [11/2021 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  19

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

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  19

  15. 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  17

    Result: 

    OK 

    See step  16

  16. 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 - ] 

  17. 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 

  18. 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  19

  19. CHECK WHETHER DTC OUTPUT RECURS (DTC P25B4-73) 
    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: P25B4-73.
      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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