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Home >> Toyota >> 2011 >> FJ Cruiser 4WD, Part Time >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System Diagnostic Codes (P0340 - P1603) >> SFI System >> DTC P050A: Cold Start Idle Air Control System Performance >> Procedure
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DTC P050A: Cold Start Idle Air Control System Performance: Procedure

  1. CHECK 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 Codes.
    5. Read the DTCs.
      RESULT

      Result Proceed To
      P050A is output A
      P050A and other DTCs are output B

      HINT: 

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

    B → See step   20 

    A: Go to next step 

  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 while the engine is idling.
    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

      Standard

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

    NG → See step   5 

    OK: Go to next step 

  3. INSPECT THROTTLE WITH MOTOR BODY ASSEMBLY 
    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.

    OK → See step   14 

    NG → See step   4 

  4. REPAIR OR REPLACE THROTTLE WITH MOTOR BODY ASSEMBLY 
    1. Repair or replace throttle with motor body assembly. Refer to REMOVAL .

    NEXT → See step   14 

  5. CHECK PCV SYSTEM 
    1. Check the PCV hose connections. Refer to COMPONENTS .

      OK

      PCV hose is connected correctly and is not damaged.

    NG → See step   10 

    OK: Go to next step 

  6. CHECK INTAKE SYSTEM. Refer to  PROCEDURE - Step 2 

    NG → See step   11 

    OK: Go to next step 

  7. INSPECT 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.

    NG → See step   12 

    OK: Go to next step 

  8. PERFORM ACTIVE TEST USING TECHSTREAM (OPERATE OCV) 
    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 System (Bank 1) or Control the VVT System (Bank 2).
    5. Check the engine speed while operating the Oil Control Valve (OCV) using the Techstream.

      OK

      Tester Operation Specified Condition
      OCV OFF Normal engine speed
      OCV ON Engine idles roughly or stalls (soon after OCV switched from OFF to ON)

    NG → See step   13 

    OK: Go to next step 

  9. READ VALUE USING TECHSTREAM (MAF). Refer to  PROCEDURE - Step 6 

    OK → See step   14 

    NG → See step   15 

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

    NEXT → See step   14 

  11. REPAIR OR REPLACE INTAKE SYSTEM 
    1. Repair or replace intake system. Refer to ON-VEHICLE INSPECTION .

    NEXT → See step   14 

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

    NEXT → See step   14 

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

    NEXT: Go to next step 

  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 the DTCs. Refer to DTC CHECK / CLEAR .
    5. Turn the ignition switch off and wait for at least 30 seconds.
    6. Turn the ignition switch to ON and turn the Techstream on.
    7. Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.
    8. Check that the engine coolant temperature is between -10°C and 50°C (14 and 122°F).
    9. Start the engine and warm it up.
    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

    B → See step   15 

    A → See step   21 

  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 .

      HINT: 

      Repair any problems.

    NEXT: Go to next step 

  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 the DTCs. Refer to DTC CHECK / CLEAR .
    5. Turn the ignition switch off.
    6. Turn the ignition switch to ON and turn the Techstream on.
    7. Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.
    8. Check that the engine coolant temperature is between -10°C and 50°C (14 and 122°F).
    9. Start the engine and warm it up.
    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

    B → See step   17 

    A → END 

  17. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM). Refer to  PROCEDURE - Step 29 

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  18. REPLACE MASS AIR FLOW METER ASSEMBLY 
    1. Replace the mass air flow meter assembly. Refer to REMOVAL .

      HINT: 

      If the result of the inspection performed in step 9 indicated no problem, proceed to the next step without replacing the mass air flow meter assembly.

    NEXT: Go to next step 

  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 .
    5. Turn the ignition switch off.
    6. Turn the ignition switch to ON and turn the Techstream on.
    7. Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.
    8. Check that the engine coolant temperature is between -10°C and 50°C (14 and 122°F).
    9. Start the engine and warm it up.
    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

    B → See step   22 

    A → END 

  20. GO TO DTC CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART 
  21. CHECK FOR INTERMITTENT PROBLEMS. Refer to  CHECK FOR INTERMITTENT PROBLEMS 
  22. REPLACE ECM. Refer to  REMOVAL 
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