DTC P050A-00: Cold Start Idle Control System Performance [03/2023 - ]: Procedure

1. Read the DTCs.

   Powertrain > Engine > Trouble Codes 

   Result

   Result	Proceed to
   P050A-00 and other DTCs are output	A
   P050A-00 is output	B

   HINT: 

   If any DTCs other than P050A-00 are output, troubleshoot those DTCs first.

Result: 

A 

GO TO DTC CHART 

Result: 

B 

See step  2

HINT: 

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

Pre-procedure1

• Put the engine in Inspection Mode (Maintenance Mode).

  Powertrain > Hybrid Control > Utility 

  Tester Display
  Inspection Mode

• Start the engine.

• Read the values displayed on the GTS at engine idle.

  Powertrain > Engine > Data List 

  Tester Display
  Short FT B1S1
  Long FT B1S1

• Add the Short FT B1S1 and Long FT B1S1 values to obtain the total fuel trim.

  Result

  Result	Proceed to
  The sum of the value of Short FT B1S1 and Long FT B1S1 is -20 % or more, and less than 20 %	A
  None of the above conditions are met	B

Post-procedure1

• None.

Result: 

B 

See step  7

Result: 

A 

See step  3

1. Check for foreign matter between the throttle valve and housing. If necessary, clean the throttle body with motor assembly. Also, check that the throttle valve moves smoothly.

   OK

   Throttle valve is not contaminated with foreign matter and moves smoothly.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

See step  6

Result: 

OK 

See step  4

Pre-procedure1

• Put the engine in Inspection Mode (Maintenance Mode).

  Powertrain > Hybrid Control > Utility 

  Tester Display
  Inspection Mode

• Start the engine and warm it up until the engine coolant temperature is 75°C (167°F) or higher.

  Powertrain > Engine > Data List 

  Tester Display
  Coolant Temperature

  HINT: 

  The A/C switch and all accessories should be off.

• Confirm that the value of Data List item Engine Independent is "Operate" then check the value of Intake Manifold Absolute Pressure while performing the Active Test.

  Powertrain > Engine > Active Test 

  Active Test Display
  Control the EGR Step Position

  Data List Display
  Intake Manifold Absolute Pressure
  Engine Independent

  NOTE:

  • Make sure that the value of Data List item Engine Independent is "Operate" while performing the Active Test.
  • Do not leave the EGR valve open for 10 seconds or more during the Active Test.
  • Be sure to return the EGR valve to step 0 when the Active Test is completed.
  • Do not open the EGR valve 30 steps or more during the Active Test.

  OK

  The value of Intake Manifold Absolute Pressure changes in response to the EGR step position when the value of Engine Independent is "Operate".

  Standard

  -	Control the EGR Step Position (Active Test)
  	0 Steps	0 to 30 Steps
  Intake Manifold Absolute Pressure (Data List)	(EGR valve is fully closed)	Intake Manifold Absolute Pressure value is at least +10 kPa (1.45 psi) higher than when EGR valve is fully closed

  HINT: 

  • If the value of Data List item Engine Independent is "Not Opr" when the engine is idling, charge control is being performed. Perform the Active Test after charge control is complete ("Operate" is displayed).
  • While performing the Active Test, if the increase in the value of Intake Manifold Absolute Pressure is small, the EGR valve assembly may be malfunctioning.
  • Even if the EGR valve assembly is malfunctioning, rough idling or an increase in the value of Intake Manifold Absolute Pressure may occur while performing the Active Test. However, the amount that the value of Intake Manifold Absolute Pressure increases will be smaller than normal.

  Result

  Result	Proceed to
  Intake Manifold Absolute Pressure value is at least +10 kPa (1.45 psi) higher than when EGR valve is fully closed	A
  None of the above conditions are met	B

Post-procedure1

• None.

Result: 

A 

See step  15

Result: 

B 

See step  5

Pre-procedure1

• Remove the EGR valve assembly.

  HINT: 

  Refer to REMOVAL [03/2023 - ]

• Check if the EGR valve is stuck open.

  OK

  EGR valve is tightly closed.

  Result

  Proceed to
  OK
  NG

Post-procedure1

• None.

Result: 

OK 

See step  15

Result: 

NG 

See step  27

HINT: 

Refer to REMOVAL [12/2022 - ]

Result

Result: 

NEXT 

See step  32

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Check the PCV hose connections.
2. Check the PCV valve.

   Refer to INSPECTION [12/2022 - ]

   OK

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

   Result

   Proceed to
   OK
   NG

Result: 

NG 

See step  31

Result: 

OK 

See step  8

1. Check the intake system for vacuum leaks.

   Refer to ON-VEHICLE INSPECTION [12/2022 - ]

   OK

   No leaks from intake system.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

See step  30

Result: 

OK 

See step  9

1. Visually check that the air cleaner filter element sub-assembly is not excessively contaminated with dirt or oil.

   OK

   The air cleaner filter element sub-assembly is not excessively contaminated with dirt or oil.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

See step  29

Result: 

OK 

See step  10

Pre-procedure1

• Put the engine in Inspection Mode (Maintenance Mode).

  Powertrain > Hybrid Control > Utility 

  Tester Display
  Inspection Mode

• Start the engine and warm it up until the engine coolant temperature is 75°C (167°F) or higher.

  Powertrain > Engine > Data List 

  Tester Display
  Coolant Temperature

  HINT: 

  The A/C switch and all accessories should be off.

• Confirm that the value of Data List item Engine Independent is "Operate" then check the value of Intake Manifold Absolute Pressure while performing the Active Test.

  Powertrain > Engine > Active Test 

  Active Test Display
  Control the EGR Step Position

  Data List Display
  Intake Manifold Absolute Pressure
  Engine Independent

  NOTE:

  • Make sure that the value of Data List item Engine Independent is "Operate" while performing the Active Test.
  • Do not leave the EGR valve open for 10 seconds or more during the Active Test.
  • Be sure to return the EGR valve to step 0 when the Active Test is completed.
  • Do not open the EGR valve 30 steps or more during the Active Test.

  OK

  The value of Intake Manifold Absolute Pressure changes in response to the EGR step position when the value of Engine Independent is "Operate".

  Standard

  -	Control the EGR Step Position (Active Test)
  	0 Steps	0 to 30 Steps
  Intake Manifold Absolute Pressure (Data List)	(EGR valve is fully closed)	Intake Manifold Absolute Pressure value is at least +10 kPa (1.45 psi) higher than when EGR valve is fully closed

  HINT: 

  • If the value of Data List item Engine Independent is "Not Opr" when the engine is idling, charge control is being performed. Perform the Active Test after charge control is complete ("Operate" is displayed).
  • While performing the Active Test, if the increase in the value of Intake Manifold Absolute Pressure is small, the EGR valve assembly may be malfunctioning.
  • Even if the EGR valve assembly is malfunctioning, rough idling or an increase in the value of Intake Manifold Absolute Pressure may occur while performing the Active Test. However, the amount that the value of Intake Manifold Absolute Pressure increases will be smaller than normal.

  Result

  Result	Proceed to
  Intake Manifold Absolute Pressure value is at least +10 kPa (1.45 psi) higher than when EGR valve is fully closed	A
  None of the above conditions are met	B

Post-procedure1

• None.

Result: 

A 

See step  12

Result: 

B 

See step  11

Pre-procedure1

• Remove the EGR valve assembly.

  HINT: 

  Refer to REMOVAL [03/2023 - ]

• Check if the EGR valve is stuck open.

  OK

  EGR valve is tightly closed.

  Result

  Proceed to
  OK
  NG

Post-procedure1

• None.

Result: 

NG 

See step  27

Result: 

OK 

See step  12

Pre-procedure1

• Remove the EFI NO. 1 fuse from the No. 1 engine room relay block and No. 1 junction block assembly and wait for at least 60 seconds.

  HINT: 

  Clear the DTC without using the GTS.

• Reinstall the EFI NO. 1 fuse.
• Put the engine in Inspection Mode (Maintenance Mode).

  Powertrain > Hybrid Control > Utility 

  Tester Display
  Inspection Mode

• Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.

  Powertrain > Engine > Data List 

  Tester Display
  Coolant Temperature

  HINT: 

  The A/C switch and all accessories should be off.

• Read the Data List while performing the Active Test with the engine idling.

  Powertrain > Engine > Active Test 

  Active Test Display
  Control the VVT-iE Opening Angle Bank 1

  Data List Display
  Intake VVT Change Angle Bank 1
  Intake VVT Target Angle Bank 1

  Standard

  Active Test Movement Order	Difference between "Intake VVT Change Angle Bank 1" and "Intake VVT Target Angle Bank 1"
  0 deg → 10 deg → 20 deg → 40 deg → 0 deg → 10 deg → END	Within 4 DegFR

  Result

  Proceed to
  OK
  NG

Post-procedure1

• None

Result: 

NG 

See step  24

Result: 

OK 

See step  13

Refer to PROCEDURE - Step 2

Result

Result: 

NG 

See step  17

Result: 

OK 

See step  14

Pre-procedure1

• Put the engine in Inspection Mode (Maintenance Mode).

  Powertrain > Hybrid Control > Utility 

  Tester Display
  Inspection Mode

• Start the engine.
• Allow the engine to idle until Coolant Temperature is 75°C (167°F) or higher.

  Powertrain > Engine > Data List 

  Tester Display
  Coolant Temperature

• Read Mass Air Flow Sensor while maintaining an engine speed of 2500 RPM.

  Powertrain > Engine > Data List 

  Tester Display
  Calculate Load
  Mass Air Flow Sensor

  HINT: 

  During charge control, the engine speed is set at idle. Therefore, the engine speed will not increase when the accelerator pedal is depressed. In this case, read the Data List after charge control has completed.

  Standard

  GTS Display	Condition	Specified Condition
  Mass Air Flow Sensor	Engine warmed up Shift position: P A/C: Off Engine Speed: 2500 RPM	Between 5.5 and 18.6 gm/sec

  Result

  Result	Proceed to
  The value of Mass Air Flow Sensor is between 5.5 and 18.6 gm/sec	A
  None of the above conditions are met	B

Post-procedure1

• None.

Result: 

B 

See step  34

Result: 

A 

See step  15

Pre-procedure1

• None.

• Clear the DTCs.

  Powertrain > Engine > Clear DTCs 

  Result

  Proceed to
  NEXT

Post-procedure1

• Turn the ignition switch off and wait for at least 30 seconds.

Result: 

NEXT 

See step  16

Pre-procedure1

• Check that the engine coolant temperature is between -10 and 50°C (14 and 122°F).

  Powertrain > Engine > Data List 

  Tester Display
  Coolant Temperature

• Put the engine in Inspection Mode (Maintenance Mode).

  Powertrain > Hybrid Control > Utility 

  Tester Display
  Inspection Mode

• Start the engine and warm it up until the engine coolant temperature is the same as the engine coolant temperature in the Freeze Frame Data.
• Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

• Check the DTC judgment result.

  Powertrain > Engine > Utility 

  Tester Display
  All Readiness

• Input the DTC: P050A-00.

  Result

  Result	Proceed to
  NORMAL (DTCs are not output)	A
  ABNORMAL (DTC P050A-00 is output)	B

Post-procedure1

• None.

Result: 

A 

CHECK FOR INTERMITTENT PROBLEMS 

Refer to CHECK FOR INTERMITTENT PROBLEMS [12/2022 - ]

Result: 

B 

See step  34

Refer to PROCEDURE - Step 5

Result

Result: 

NG 

See step  22

Result: 

OK 

See step  18

Refer to PROCEDURE - Step 6

Result

Result: 

NG 

See step  25

Result: 

OK 

See step  19

Refer to PROCEDURE - Step 7

Result

Result: 

OK 

See step  28

Result: 

NG 

See step  20

Refer to PROCEDURE - Step 8

Result

Result: 

OK 

See step  32

Result: 

NG 

See step  21

1. Repair or replace malfunctioning parts, component and area.

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  32

Refer to PROCEDURE - Step 11

Result

Result: 

NEXT 

See step  23

Refer to PROCEDURE - Step 6

Result

Result: 

OK 

See step  26

Result: 

NG 

See step  25

Refer to PROCEDURE - Step 2

Result

Result: 

NEXT 

See step  32

Refer to PROCEDURE - Step 6

Result

Result: 

NEXT 

See step  26

Refer to PROCEDURE - Step 2

Result

Result: 

OK 

See step  32

Result: 

NG 

See step  28

HINT: 

Refer to REMOVAL [03/2023 - ]

Result

Result: 

NEXT 

See step  32

Refer to PROCEDURE - Step 15

Result

Result: 

NEXT 

See step  32

1. Replace the air cleaner filter element sub-assembly.

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  32

1. Repair or replace the intake system.

   HINT: 

   Perform "Inspection After Repair" after repairing or replacing the intake system.

   Refer to INITIALIZATION [03/2023 - ]

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  32

1. Repair or replace the PCV valve or hose.

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  32

Pre-procedure1

• None.

• Clear the DTCs.

  Powertrain > Engine > Clear DTCs 

  Result

  Proceed to
  NEXT

Post-procedure1

• Turn the ignition switch off and wait for at least 30 seconds.

Result: 

NEXT 

See step  33

Pre-procedure1

• Check that the engine coolant temperature is between -10 and 50°C (14 and 122°F).

  Powertrain > Engine > Data List 

  Tester Display
  Coolant Temperature

• Put the engine in Inspection Mode (Maintenance Mode).

  Powertrain > Hybrid Control > Utility 

  Tester Display
  Inspection Mode

• Start the engine and warm it up until the engine coolant temperature is the same as the engine coolant temperature in the Freeze Frame Data.
• Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

• Check the DTC judgment result.

  Powertrain > Engine > Utility 

  Tester Display
  All Readiness

• Input the DTC: P050A-00.

  Result

  Result	Proceed to
  NORMAL (DTCs are not output)	A
  ABNORMAL (DTC P050A-00 is output)	B

Post-procedure1

• None.

Result: 

A 

END 

Result: 

B 

See step  34

1. Check the connection and terminal contact pressure of connectors and wire harnesses between the mass air flow meter sub-assembly and ECM.

   HINT: 

   • Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [12/2022 - ]
   • Repair any problems.

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  35

Pre-procedure1

• None.

• Clear the DTCs.

  Powertrain > Engine > Clear DTCs 

  Result

  Proceed to
  NEXT

Post-procedure1

• Turn the ignition switch off and wait for at least 30 seconds.

Result: 

NEXT 

See step  36

Pre-procedure1

• Check that the engine coolant temperature is between -10 and 50°C (14 and 122°F).

  Powertrain > Engine > Data List 

  Tester Display
  Coolant Temperature

• Put the engine in Inspection Mode (Maintenance Mode).

  Powertrain > Hybrid Control > Utility 

  Tester Display
  Inspection Mode

• Start the engine and warm it up until the engine coolant temperature is the same as the engine coolant temperature in the Freeze Frame Data.
• Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

• Check the DTC judgment result.

  Powertrain > Engine > Utility 

  Tester Display
  All Readiness

• Input the DTC: P050A-00.

  Result

  Result	Proceed to
  NORMAL (DTCs are not output)	A
  ABNORMAL (DTC P050A-00 is output)	B

Post-procedure1

• None.

Result: 

A 

END 

Result: 

B 

See step  37

Pre-procedure1

• Disconnect the mass air flow meter sub-assembly connector.
• Disconnect the ECM connector.

• Measure the resistance according to the value(s) in the table below.

  Standard Resistance

  Tester Connection	Condition	Specified Condition	Result
  C27-4 (VCC) - C52-78 (VCVG)	Always	Below 1 Ω	Ω
  C27-3 (FG) - C52-101 (VG)	Always	Below 1 Ω	Ω
  C27-2 (E2G) - C52-79 (E2G)	Always	Below 1 Ω	Ω
  C27-4 (VCC) or C52-78 (VCVG) - Body ground and other terminals	Always	10 kΩ or higher	kΩ
  C27-3 (FG) or C52-101 (VG) - Body ground and other terminals	Always	10 kΩ or higher	kΩ
  C27-2 (E2G) or C52-79 (E2G) - Body ground and other terminals	Always	10 kΩ or higher	kΩ

  Result

  Proceed to
  OK
  NG

Post-procedure1

• None.

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  38

HINT: 

• Refer to REMOVAL [12/2022 - ]
• If the result of the inspection performed in step 14 (READ VALUE USING GTS (MASS AIR FLOW SENSOR)) indicated no problem, proceed to the next step without replacing the mass air flow meter sub-assembly.

Result

Result: 

NEXT 

See step  39

Pre-procedure1

• None.

• Clear the DTCs.

  Powertrain > Engine > Clear DTCs 

  Result

  Proceed to
  NEXT

Post-procedure1

• Turn the ignition switch off and wait for at least 30 seconds.

Result: 

NEXT 

See step  40

Pre-procedure1

• Check that the engine coolant temperature is between -10 and 50°C (14 and 122°F).

  Powertrain > Engine > Data List 

  Tester Display
  Coolant Temperature

• Put the engine in Inspection Mode (Maintenance Mode).

  Powertrain > Hybrid Control > Utility 

  Tester Display
  Inspection Mode

• Start the engine and warm it up until the engine coolant temperature is the same as the engine coolant temperature in the Freeze Frame Data.
• Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

• Check the DTC judgment result.

  Powertrain > Engine > Utility 

  Tester Display
  All Readiness

• Input the DTC: P050A-00.

  Result

  Result	Proceed to
  NORMAL (DTCs are not output)	A
  ABNORMAL (DTC P050A-00 is output)	B

Post-procedure1

• None.

Result: 

A 

END 

Result: 

B 

REPLACE ECM 

Refer to REMOVAL [03/2023 - ]