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Home >> Toyota >> 2017 >> 4Runner TRD Pro >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Diagnostic Codes (P0416-P0550) >> SFI System >> DTC P050A: Cold Start Idle Air Control System Performance [08/2015 - 08/2019] >> Procedure
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DTC P050A: Cold Start Idle Air Control System Performance [08/2015 - 08/2019]: Procedure

  1. CHECK FOR ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P050A) 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine and ECT / Trouble Code.
    5. Read the DTCs.
      RESULT

      Display (DTC Output) Proceed to
      P050A A
      P050A and other DTCs B

      HINT: 

      If any DTCs other than P050A are output, troubleshoot those DTCs first.

    Result: 

    B 

    GO TO DTC CHART 

    (Refer to DIAGNOSTIC TROUBLE CODE CHART [08/2015 - 08/2019] )

    Result: 

    A 

    See step  2

  2. READ VALUE USING TECHSTREAM (FUEL TRIM) 

    HINT: 

    Calculate the total fuel trim values to check the characteristic deviation of the mass air flow meter.

    1. Connect the Techstream to the DLC3.
    2. Start the engine.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine and ECT / Data List / Short FT #1 and Long FT #1, or Short FT #2 and Long FT #2.
    5. Read the values displayed on the Techstream.
    6. Add together the Short FT #1 and Long FT #1, or Short FT #2 and Long FT #2 values to obtain the total fuel trim.

      OK

      Total of Short FT #1 and Long FT #1, or Short FT #2 and Long FT #2 values is between -20% and 20%.

    Result: 

    NG 

    See step  5

    Result: 

    OK 

    See step  3

  3. INSPECT THROTTLE VALVE 
    1. Check for deposits around the throttle valve, and check the throttle valve condition.

      OK

      No deposits around throttle valve and throttle valve moves smoothly.

    Result: 

    OK 

    See step  14

    Result: 

    NG 

    See step  4

  4. REPAIR OR REPLACE THROTTLE BODY WITH MOTOR ASSEMBLY 
    1. Repair or replace the throttle body with motor assembly (Refer to REMOVAL [08/2015 - ] ).

    Result: 

    NEXT 

    See step  14

  5. CHECK PCV HOSE CONNECTIONS 
    1. Check the PCV hose connections.

      OK

      PCV hose is connected correctly and is not damaged.

    Result: 

    NG 

    See step  10

    Result: 

    OK 

    See step  6

  6. CHECK AIR INDUCTION SYSTEM 
    1. Check the air induction system for vacuum leakage.

      OK

      No leakage from air induction system.

    Result: 

    NG 

    See step  11

    Result: 

    OK 

    See step  7

  7. CHECK AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY 
    1. Visually check that the air cleaner filter element is not excessively contaminated with dirt or oil.

      OK

      Air cleaner filter element is not excessively contaminated with dirt or oil.

    Result: 

    NG 

    See step  12

    Result: 

    OK 

    See step  8

  8. PERFORM ACTIVE TEST USING TECHSTREAM (OPERATE CAMSHAFT TIMING OIL CONTROL VALVE) 
    1. Connect the Techstream to the DLC3.
    2. Start the engine and turn the Techstream on.
    3. Warm up the engine.
    4. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the VVT Linear (Bank 1) or Control the VVT Linear (Bank 2).
    5. Check the engine speed while operating the camshaft timing oil control valve using the Techstream.

      OK

      Tester Operation Specified Condition
      0% (OFF) Normal engine speed
      127% (ON) Engine idles roughly or stalls
      (soon after camshaft timing oil control valve switched from OFF to ON)

      HINT: 

      Refer to "Data List / Active Test" [VVT OCV Duty #1, VVT Change Angle #1, VVT OCV Duty #2 and VVT Change Angle #2] (Refer to DATA LIST / ACTIVE TEST [08/2015 - 08/2019] ).

    Result: 

    NG 

    See step  13

    Result: 

    OK 

    See step  9

  9. READ VALUE USING TECHSTREAM (MAF) 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / MAF, Coolant Temp and Engine Speed.
    5. Allow the engine to idle until Coolant Temp reaches 75°C (167°F) or higher.
    6. Read MAF with the engine speed at 3000 rpm.

      Standard

      Between 13.8 g/sec. and 17.3 g/sec. (shift lever: N; A/C: Off).

    Result: 

    OK 

    See step  14

    Result: 

    NG 

    See step  15

  10. REPAIR OR REPLACE PCV HOSE 
    1. Repair or replace the PCV hose.

    Result: 

    NEXT 

    See step  14

  11. REPAIR OR REPLACE AIR INDUCTION SYSTEM 
    1. Repair or replace the air induction system.

    Result: 

    NEXT 

    See step  14

  12. REPLACE AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY 
    1. Replace air cleaner filter element sub-assembly.

    Result: 

    NEXT 

    See step  14

  13. CHECK AND REPAIR VVT SYSTEM 
    1. Check and repair the VVT system.

      HINT: 

      Refer to DTC P0011 Inspection Procedure (Refer to DTC P0011: Camshaft Position "A" - Timing Over-Advanced or System Performance (Bank 1); DTC P0012: Camshaft Position "A" - Timing Over-Retarded (Bank 1); DTC P0021: Camshaft Position "A" - Timing Over-Advanced or System Performance (Bank 2); DTC P0022: Camshaft Position "A" - Timing Over-Retarded (Bank 2) [08/2015 - ] ).

    Result: 

    NEXT 

    See step  14

  14. CHECK WHETHER DTC OUTPUT RECURS (DTC P050A) 
    NOTE:

    In this operation, the engine must be cold (the same level as the engine coolant temperature recorded in the freeze frame data).

    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the Techstream on.
    4. Clear DTCs (Refer to DTC CHECK / CLEAR [08/2015 - 08/2019] ).
    5. Turn the ignition switch off and wait for at least 30 seconds.
    6. Turn the ignition switch to ON.
    7. Turn the Techstream on.
    8. Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.
    9. Check that the engine coolant temperature is between -10°C and 50°C (14 and 122°F).
    10. Start the engine and warm it up.
    11. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
    12. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
    13. Input the DTC: P050A.
    14. Check the DTC judgment result.
      RESULT

      Result Proceed to
      ABNORMAL (DTC P050A is output) A
      NORMAL (DTC is not output) B

    Result: 

    B 

    CHECK FOR INTERMITTENT PROBLEMS 

    (Refer to CHECK FOR INTERMITTENT PROBLEMS [08/2015 - ] )

    Result: 

    A 

    See step  15

  15. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER CONNECTOR CONNECTION) 
    1. Check the connection and terminal contact pressure of connectors and wire harnesses between the mass air flow meter and ECM (Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [08/2015 - ] ).

      HINT: 

      Repair any problems.

    Result: 

    NEXT 

    See step  16

  16. CHECK WHETHER DTC OUTPUT RECURS (DTC P050A) 
    NOTE:

    In this operation, the engine must be cold (approximately the same as the engine coolant temperature recorded in the freeze frame data).

    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the Techstream on.
    4. Clear DTCs (Refer to DTC CHECK / CLEAR [08/2015 - 08/2019] ).
    5. Turn the ignition switch off and wait for at least 30 seconds.
    6. Turn the ignition switch to ON.
    7. Turn the Techstream on.
    8. Start the engine.
    9. Warm up the engine.
    10. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
    11. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
    12. Input the DTC: P050A.
    13. Check the DTC judgment result.
      RESULT

      Result Proceed to
      ABNORMAL (DTC P050A is output) A
      NORMAL (DTC is not output) B

    Result: 

    B 

    END 

    Result: 

    A 

    See step  17

  17. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM) 
    1. Disconnect the mass air flow meter 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
      B35-5 (VG) - B37-14 (VG) Always Below 1 Ω
      B35-4 (E2G) - B37-13 (E2G) Always Below 1 Ω
      B35-5 (VG) or B37-14 (VG) - Body ground Always 10 kΩ or higher
    4. Reconnect the mass air flow meter connector.
    5. Reconnect the ECM connector.

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (MASS AIR FLOW METER - ECM) 

    Result: 

    OK 

    See step  18

  18. REPAIR OR REPLACE MASS AIR FLOW METER 
    1. Replace the mass air flow meter (Refer to REMOVAL [08/2015 - ] ).

      HINT: 

      If the results of the inspections performed in steps 16 and 21 indicated no problem, proceed to the next step without replacing the mass air flow meter.

    Result: 

    NEXT 

    See step  19

  19. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED 
    NOTE:

    In this operation, the engine must be cold (approximately the same as the engine coolant temperature recorded in the freeze frame data).

    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the Techstream on.
    4. Clear DTCs (Refer to DTC CHECK / CLEAR [08/2015 - 08/2019] ).
    5. Turn the ignition switch off and wait for at least 30 seconds.
    6. Turn the ignition switch to ON.
    7. Turn the Techstream on.
    8. Start the engine.
    9. Warm up the engine.
    10. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
    11. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
    12. Input the DTC: P050A.
    13. Check the DTC judgment result.
      RESULT

      Result Proceed to
      NORMAL (DTC is not output) A
      ABNORMAL (DTC P050A is output) B

    Result: 

    A 

    END 

    Result: 

    B 

    REPLACE ECM 

    (Refer to REMOVAL [08/2015 - ] )

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