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Home >> Toyota >> 2020 >> 86 Base, Standard Trans >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System - Diagnostic Codes (4 Of 6) >> SFI System >> DTC P050A: Cold Start Idle Air Control System Performance; DTC P050B: Cold Start Ignition Timing Performance [06/2016 - 12/2017] >> Procedure
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DTC P050A: Cold Start Idle Air Control System Performance; DTC P050B: Cold Start Ignition Timing Performance [06/2016 - 12/2017]: Procedure

  1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P050A OR P050B) 
    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 / Trouble Codes.
    5. Read DTCs.
      RESULT

      Result Proceed to
      DTC P050A or P050B is output A
      DTC P050A or P050B and other DTCs are output B

      HINT: 

      If any DTCs other than P050A or P050B are output, troubleshoot those DTCs first.

    Result: 

    B 

    GO TO DTC CHART 

    (Refer to DIAGNOSTIC TROUBLE CODE CHART [06/2016 - 03/2017] , or refer to DIAGNOSTIC TROUBLE CODE CHART [03/2017 - 07/2018] )

    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 / Data List / Short FT #1 and Long FT #1.
    5. Read the values displayed on the Techstream at engine idle.
    6. Add together the Short FT #1 and Long FT #1 values to obtain the total fuel trim.

      Standard

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

    Result: 

    NG 

    See step  5

    Result: 

    OK 

    See step  3

  3. INSPECT THROTTLE WITH MOTOR BODY ASSEMBLY (THROTTLE VALVE) 
    1. Check that there are no deposits around the throttle valve and throttle valve condition.

      OK

      No deposits around the throttle valve and throttle valve moves smoothly.

      RESULT

      Result Proceed to
      NG A
      OK B

    Result: 

    B 

    See step  14

    Result: 

    A 

    See step  4

  4. REPLACE THROTTLE WITH MOTOR BODY ASSEMBLY 
    1. Replace the throttle with motor body assembly (Refer to REMOVAL [06/2016 - ] ).

    Result: 

    NEXT 

    See step  14

  5. CHECK PCV SYSTEM 
    1. Check the PCV hose connections (Refer to ON-VEHICLE INSPECTION [06/2016 - ] ).

      OK

      PCV valve and hose are connected correctly and are not damaged.

    Result: 

    NG 

    See step  10

    Result: 

    OK 

    See step  6

  6. CHECK INTAKE SYSTEM 
    1. Check the intake system for vacuum leaks (Refer to ON-VEHICLE INSPECTION [06/2016 - ] ).

      OK

      No leaks from the intake 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

      The 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. Operate the VVT system through the Active test, and check if the VVT system is operating normally.
      1. Perform the Active Test, referring to DTC P000A inspection procedure (VVT system for intake camshaft) (Refer to PROCEDURE - Step 2 ).
      2. Perform the Active Test, referring to DTC P000B inspection procedure (VVT system for exhaust camshaft) (Refer to PROCEDURE - Step 2 ).

    Result: 

    NG 

    See step  13

    Result: 

    OK 

    See step  9

  9. READ VALUE USING TECHSTREAM (MAF) 

    Refer to PROCEDURE - Step 14

    Result: 

    OK 

    See step  14

    Result: 

    NG 

    See step  15

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

    Result: 

    NEXT 

    See step  14

  11. REPAIR OR REPLACE INTAKE SYSTEM 
    1. Repair or replace the intake system.

    Result: 

    NEXT 

    See step  14

  12. REPLACE AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY 
    1. Replace the air cleaner filter element sub-assembly (Refer to PROCEDURE - Step 2 ).

    Result: 

    NEXT 

    See step  14

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

      HINT: 

    Result: 

    NEXT 

    See step  14

  14. CHECK WHETHER DTC OUTPUT RECURS (DTC P050A OR P050B) 
    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 the DTCs (Refer to DTC CHECK / CLEAR [06/2016 - ] ).
    5. Turn the ignition switch off and wait for at least 30 seconds.
    6. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
    7. Enter the following menus: Powertrain / Engine / Utility / All Readiness.
    8. Input the DTC: P050A or P050B.
    9. Check the DTC judgment result.
      RESULT

      Result Proceed to
      NORMAL (DTC is not output) A
      ABNORMAL (DTC P050A or P050B is output) B

    Result: 

    A 

    CHECK FOR INTERMITTENT PROBLEMS 

    (Refer to CHECK FOR INTERMITTENT PROBLEMS [06/2016 - ] )

    Result: 

    B 

    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 [06/2016 - ] ).

      HINT: 

      Repair any problems.

    Result: 

    NEXT 

    See step  16

  16. CHECK WHETHER DTC OUTPUT RECURS (DTC P050A OR P050B) 
    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 the DTCs (Refer to DTC CHECK / CLEAR [06/2016 - ] ).
    5. Turn the ignition switch off and wait for at least 30 seconds.
    6. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
    7. Enter the following menus: Powertrain / Engine / Utility / All Readiness.
    8. Input the DTC: P050A or P050B.
    9. Check the DTC judgment result.
      RESULT

      Result Proceed to
      ABNORMAL (DTC P050A or P050B 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) 

    Refer to PROCEDURE - Step 3

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  18

  18. REPLACE MASS AIR FLOW METER 
    1. Replace the mass air flow meter (Refer to REMOVAL [06/2016 - ] ).

      HINT: 

      If the results of the inspections performed in step 9 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 the DTCs (Refer to DTC CHECK / CLEAR [06/2016 - ] ).
    5. Turn the ignition switch off and wait for at least 30 seconds.
    6. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
    7. Enter the following menus: Powertrain / Engine / Utility / All Readiness.
    8. Input the DTC: P050A or P50B.
    9. Check the DTC judgment result.
      RESULT

      Result Proceed to
      NORMAL (DTC is not output) A
      ABNORMAL (DTC P050A or P050B is output) B

    Result: 

    A 

    END 

    Result: 

    B 

    REPLACE ECM 

    (Refer to REMOVAL [06/2016 - ] )

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